What if I don’t know my trusted phone number anymore but it is required?

If you are using Mac OS catalina 10.15.7 or above versions .

Open appleid.apple.com a pop up window will appear , click on continue with password , enter admin password .

Second method is open system preferences > click on Apple ID icon > in the side bar section click on password and security .

Click on edit .

The phone numbers that are verified are visible .

You can sign in with appleid.apple.com with account credentials from a web browser in account security click on the icon it will show the trusted number .