There may be a few different cases when the customer wouldn't be able to receive the SMS code when trying to register in the app or logging back into it after having logged out before. Below we'll look at the most common scenarios and solutions.

Case 1.

Problem: After client enters their registration/login details, they get redirected to the SMS code input screen and afterwards nothing happens - no SMS is delivered to their phone number, but they also get no error message.

Solution: Check your OTP merchant account balance (e.g. your Dexatel or Twilio account) - most probably it has been depleted and requires topping up. Additional advice is to set automatic account top-up if your OTP provider supports this functionality (possible on Twilio and Dexatel already).

Case 2.

Problem: After client enters their registration/login details, they do not get redirected to the SMS code input screen and receive an error message saying: "Limit of request reached. Please try again later."

Solution: There may be a number of reasons for this error showing up, you can read more details for different scenarios here.

Case 3.

Problem: After client enters their registration/login details, they do not get redirected to the SMS code input screen and receive an error message saying: "Phone number you entered is incorrect."

Solution: Ask the client to double-check if they have made any typos during phone number entry or have any blank spaces added by mistake. If the number is being entered correctly, double-check with your OTP service provider's support team if the country code of the client's phone number is not blocked by the service provider or if perhaps they see any other issue with the particular phone number for verification.