I’ve seen a topic about this from 2 years ago. None of those solutions is helping me. I’m trying to add iHeartRadio to my Sonos services. The Sonos app tells I need to authorize the service and gives me a 5 digit code to enter. It then sends me off to Safari to enter this code. However, it appears the phone is auto-filling that 5 digit number for me (perhaps incorrectly?) - but then the web page tells me that I did indeed successfully authorize my Sonos system to my iHeartRadio account. So I’m pretty sure the code was entered correctly.
The problem is when I try to use iHeartRadio it constantly tells me that the account needs authorized. This is very frustrating.