After changing your phone number you will need to download the Mexem app and will not be able to receive the SMS verification anymore.
The first step is to change the phone number in the client portal mexem.com.
Steps:
1. Go to mexem.com
2. Log in
2. Click on Welcome
3. Go to Settings
At Communication (right side) you will need to change and verify the new phone number.
After doing this you will need to download the MEXEM App on your phone and register the 2 factor.