If you do not receive an incoming authorization call or SMS code when you log in or register in the app again, here are some steps you can take:
Try just waiting a few minutes: Sometimes there may be temporary delays in SMS delivery.
Check your phone number: Make sure you have entered your phone number correctly.
Check blocked numbers: Make sure you don't have blocked calls / SMS in your phone settings.
If you have two SIM cards, make sure the code is sent to the active one.
Check whether the SIM card in the other phone is working.
Ensure the device memory is not full.
Check the signal on your phone: Make sure you have a stable network connection.
Verify everything is OK with the SIM card and mobile network (check with your operator).
Try restarting your device.
If the problem persists, consider using a different login method. (If no call is received, try selecting SMS and vice versa)