For some time I was not able to secure my Twitter account and other online services with a two factor authentication security. This means I wanted to have :
1) user & password
2) code sent to my phone by text message
Today I invested again some time and reached out to the Business Team via chat. Angie was awesome and after checking several system settings on T-Mobile end, she found out that all short numbers were blocked on my account. Twitter typically sends from "40 404".
Once this blocking was deactivated, 30 seconds after I tried again and could successfully activate my T-Mobile number for Twitter :-)
So I wanted to make sure to share this great news as I have been searching a while.
Thank you so much for sharing this, magenta5438803! I'm glad to read that Angie was able to get this squared away for you so that 2FA was an option, and while it's a bummer that the codes were disabled without your knowledge it's great that the fix was quick!
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