A. 1. Check your phone's signal strength. Ensure you have a good network connection. 2. Restart your phone to refresh the network connection. 3. Ensure that the phone number you provided is correct and in the correct format. 4. Wait a few minutes and request the verification code again. 5. If you still do not receive the code, try using a different phone number if possible.

B. 1. Check if your phone has any SMS blocking features enabled. Disable them if necessary. 2. Contact your mobile service provider to ensure that there are no issues with receiving SMS from international numbers.