The same happened with my Oppo app I used for my 105 /Tidal streaming. Oppo customer service said it was something on Tidals part, not theirs, and there was nothing to do about it, but as @soix pointed out, the M Connect app is now working just fine as an interface.
Tidal login problem using Oppo Sonica
Two weeks ago I tried to log in to Tidal hi-fi using my Sonica streamer but couldn’t . Since Sonica has gone out of business and hasn’t changed their software I can no longer use the streamer in my Sonica. Anyone else have this problem? I emailed Tidal and got the run around that it’s an Oppo issue but Oppo hasn’t changed anything Tidal had to have changed software. Oppo suggested using Mconnect. I looked at it but don’t know which app to select. Any other solutions?