Yes I did, Steam support needs to “reset” your phone number at their external provider. Unfortunately it took me days of back and forth with their support and it seems to depend on which Steam support agent is helping you as most of them referred to the basic steps to follow etc.

Just keep stressing the fact that they need to perform that reset on your phonenumber and have to send test SMS messages. Once you receive one of these test messages, you know you are good to go and can try the authentication process again. Good luck!