My father banks with BofA and doesn't have a cell phone, and they do call his landline to give him his 2fa authentications. Maybe he was grandfathered in somehow as he's banked with them ages and has always had that same landline. I also use Tello and got my 2fa on my cell a couple weeks ago from them, but perhaps they've done a very recent switch-up? It's absolutely zany that they create the problem by all the large corps leaking our info and we, the consumers, have to jump through hoops to access our own accounts. How long have you had that Tello number associated with your bank file? Mine was one that I ported from my old Skype account and have listed on the BofA account for over a decade. I hope that it clears up soon for you and you can find a work around.