Stream App Not Working on iPhone

I have been having an issue with the Stream App on my iPhone for months now. I have contacted customer support through chats and by phone and nobody has ever helped me. They don't understand what I am asking, and after multiple calls day after day, they just start giving made up answers because they don't know how to fix my problem. My Stream app works perfectly fine on my smart tv at home and on my phone when I am connected to Wi-Fi. When I am not connected to Wi-Fi, the shows I try to watch that I recorded don't play. The app will take forever to load and if you get the show to play, the app just closes. On occasion, I will get a "playback error TVAPP-00352". Other times, it will just keep skipping to the beginning of the show and then the picture freezes, but the sound keeps playing. I have deleted the app and reinstalled it, logged in & out, turned my phone off and on well over 20 times over the months but nothing ever works. I was told by 1 rep that they see an issue with the signal from the app to my phone and that it was the app that was the problem. Another re told me that's not something they can see. I have gotten ZERO help from customer service and have spent hours on the phone in total. This is the most frustrating situation I have ever experienced with this company. Please help me fix this issue.