Phone number not working when trying to "add a phone"

[jameson2]

Hello,

My phone number isn't working when I go to "add a phone" when trying to confirm my identity to link my bank account.  

Any ideas?  The box is red and it says, "this type of phone number isn't supported. check your number and try again".

This is a regular cell  number.  No reason it shouldn't be working.

Thanks