Blood Oxygen App Disappeared

So my Apple Watch Series 6 has recorded my blood oxygen daily I am assuming through the blood oxygen app right up until the 29th May.

I noticed it wasn’t recording and have the. Tried to locate the app, it is no longer on my watch, I have followed the advice to find it on the watch store however the app is not even showing there to download, it does on my phone but refers me back to the watch.

my health app shows it is connected and no issues present other than the last plait of data was the 29th may. What the **** is going on someone please help!