Key Takeaways
According to a report, 93% of organisations use OTP to verify user logins and payment requests. OTP codes are typically delivered via SMS for added convenience and simplicity.
However, there are times when the OTP does not arrive as expected. This not only frustrates users but also hampers the overall user experience. Understanding the reasons why OTP SMS sometimes fail to reach users is essential for service providers to mitigate these risks and ensure seamless operations.
Here Are Some Reasons Why OTP Code Doesn't Come in SMS with solutions
1. Inactive SIM Card
- Problem
One of the most common reasons why users might not receive an OTP code via SMS is that their SIM card is inactive. If the mobile number used to register for services is inactive, whether due to prolonged non-usage or SIM expiration, the delivery of SMS OTP will naturally fail. An inactive SIM card is not detectable by the network, leading it unable to receive messages, including those critical for authentication and verification.
- Solution
As an OTP SMS service provider, remind users to ensure that the phone number associated with their account is active. Incorporating automated prompts during account setup or log-in, urging users to verify their mobile number's activity, can help prevent such issues. Although this problem is primarily on the user’s end, providing timely notifications about SIM inactivity can improve the user experience.
2. Incorrect Phone Number
- Problem
Another simple yet frequent issue is entering an invalid phone number during registration or login attempts. Users often have multiple numbers or mistype a digit, resulting in the OTP code being sent to the wrong number. This not only delays the verification process but can also lead to security risks if the OTP falls into the hands of unauthorized individuals.
- Solution
When users input their phone number, consider implementing an SMS verification step to confirm the number entered is accurate.
By using SMS technology and sending a confirmation code immediately upon registration, users can rectify any errors before completing the setup. This process ensures that OTP SMS will be sent to the correct mobile number during future authentication steps.
3. Poor Network Coverage or Network Issues
- Problem
Sometimes, the fault lies not with the user or the service provider but with the cellular network. SMS delivery relies on the availability of a stable mobile network. If users are located in remote areas or regions with poor network coverage, the OTP code may not reach their device. Additionally, scheduled network maintenance or temporary outages by the cellular service provider can hinder message delivery.
- Solution
For areas with limited network coverage, service providers might consider offering alternative authentication options such as WhatsApp OTP or email verification. This gives users the flexibility to choose the method that best suits their location and available connectivity. Furthermore, for users with unstable networks, remind them that connecting to a stable Wi-Fi network and using WhatsApp for OTP can be a viable option during such scenarios.
4. Blind Spot Areas
- Problem
Blind spots or areas with little to no mobile signal, can cause significant disruption in OTP SMS delivery. These areas might exist in remote regions or dense urban environments where tall buildings obstruct mobile signals. For users in these blind spot zones, receiving SMS messages can become extremely difficult, making OTP verification near impossible.
- Solution
Encourage users to relocate temporarily to areas with better signal reception when attempting to receive an OTP SMS. Additionally, service providers can implement dynamic solutions like location-based services, which alert users to potential network issues based on their geographical location. This gives users the opportunity to address the issue proactively before OTP verification is necessary.
5. Blocked SMS Settings
- Problem
Some smartphones and mobile devices come with settings that block SMS messages from unknown or unrecognized numbers. While these settings can help prevent spam and unwanted communications, they can also prevent legitimate OTP SMS messages from being delivered.
- Solution
Encourage users to check their SMS blocking or call-blocking settings when they encounter issues receiving OTP SMS. Provide a clear and easy-to-follow guide that walks users through how to disable message blocking for unknown senders or whitelist service numbers from which OTP messages are sent. When using SMS APIs, ensure that sender IDs are configured correctly and recognizable to users, so they don’t mistake them for spam.
6. Registration Issues
- Problem
In certain regions like India, DLT (Distributed Ledger Technology) registration is mandatory for businesses sending transactional and promotional SMS. If the service provider is not properly registered under DLT SMS messages, including OTPs, might be blocked by telecom operators.
- Solution
As a service provider, ensure that you are fully compliant with DLT registration requirements. Work with telecom providers to confirm that all messaging routes are properly configured to deliver both transactional and promotional SMS.
7. Device-Related Issues
- Problem
Finally, some users might encounter device-related issues that prevent them from receiving OTP SMS. This could include outdated software, storage limitations or even malfunctions within the device’s messaging app. Additionally, users may have Do Not Disturb (DND) settings enabled, which could filter out incoming SMS messages, including OTPs.
- Solution
Offer users troubleshooting tips for checking device settings, updating their messaging app and ensuring adequate storage for incoming SMS. Educating users on how to temporarily disable DND settings during the OTP process can also help resolve these issues.
8. Sender ID Configuration Issues
• Problem
OTP SMS delivery can also fail if the sender ID is not properly configured. SMS messages are often sent from short codes or long codes and if the sender ID is not recognized or properly set up, mobile carriers might block the message. This can occur if the SMS provider is using an incorrect or unapproved sender ID.
• Solution
Ensure that sender IDs are correctly configured within your SMS API to avoid delivery failures. Whether you’re using short codes or long codes, maintaining compliance with industry standards and carrier regulations is crucial. If possible, use branded sender IDs that are easily recognizable by users to reduce the likelihood of your messages being filtered or blocked.
The Importance of OTP SMS in Authentication and Verification
- Enhanced Security
OTP SMS adds an extra layer of security by requiring a unique, time-sensitive code in addition to passwords, reducing the risk of unauthorized access.
- User Convenience
Delivered directly to a user’s mobile device, OTP SMS offers a quick and accessible verification method without the need for additional apps or hardware.
- Widespread Accessibility
Since SMS is available on almost all mobile phones, even in areas with limited internet access, OTP SMS ensures broad usability.
- Real-Time Verification
OTP SMS enables instant verification, allowing users to authenticate transactions or logins quickly without significant wait times.
- Cost-Effective for Businesses
Implementing OTP verification through SMS APIs is relatively inexpensive compared to more complex user authentication methods, making it attractive for businesses.
- Compliance with Global Standards
OTP SMS is widely used for compliance with regulatory frameworks like DLT registration, ensuring secure and traceable transactions across industries.
Conclusion
Understanding why OTP SMS might not be delivered is crucial for improving user experience and maintaining secure transactions.
Common issues include inactive SIM cards, incorrect phone numbers, poor network coverage and device settings. Addressing these problems with proactive solutions can minimize disruptions. Ensure that both users and service providers are aware of these issues and take steps to resolve them.
Send OTP SMS with Message Central
Verify Now by Message Central is an OTP service provider. The platform is trusted by fastest growing organizations across 70+ organizations. With Verify Now, you’d get: -
- OTP SMS with a global reach
- High deliverability of OTP SMS powered by direct operator connectivity
- Easy to understand, use and implement API documentation
You can sign up for free and get started.
