I have the same problem. I am able to login from the browser, but not from the phone app [iPhone XS with latest OS]. If I try to verify with either SMS or a call I just get the same 4 digit code over and over, and it does not work.
Definely all having the same issue. I emailed them yesterday with the issue and screenshot. Emailed them last night. And just emailed them AGAIN. I had no idea tech support of Airbnb was so bad. Need to figure this out ASAP!!