When you enter the mobile phone number for verification, make sure you have typed it following the international format: +country code-operator code-number. How to fix issues receiving SMS on your smartphone: 1. Your phone is switched off. Solution: Turn on the phone 2. There is no signal. Your number might be on Do Not Disturb mode or flight mode. Solution: Disable Do not disturb mode or flight mode. 3. Your phone balance is insufficient to receive/send SMS. Solution: Check your plan or credit balance to see that you have enough to send/receive messages. 4. Your carrier does not support SMS messaging. Solution: Make sure your carrier supports SMS messaging. 5. The phone settings "receive SMS messages" was turned off. Solution: Turn on the setting "receive SMS messages". 6. The sender number can be in blocklist. Solution: check the Blocklist and remove CY.SEND from it. 7. Phone does not work. Solution: Install the SIM card you are using into another working phone. If the issue persists, contact your carrier for assistance. 8. Third-party SMS messaging apps may have compatibility issues. Solution: If you are using a third-party messaging app, open Settings, search for and access Default apps, and set Messaging to Default.