First thing to check if you can login with Qobuz via Qobuz web or app.
If that is Ok, you can try to force Qobuz synchronisation in Roon again.
I had the same issue yesterday after rebuild of my server and restoring on older backup.
All my Qobuz albums were first restored and than disappeared in about 1 minute ( album counter running down)
This is how I got them back:
Go to Setup services - logout from Qobuz.
Restart Roon.
Login to Qobuz again.
Now click edit and click synchronize now.
If it finish almost immediately click again synchronize now.
Repeat until synchronize now actually starts doing something.
1st time I got some 100 albums back.
Waited 15minutes, doing the same process again.
Got me about 150 albums this time.
Repeated this during the rest of the day and after about 10 times (5 hours later) I got all my Qobuz albums back (about 1300).
I was quite dissappointed (to put it mildly) that I had to do it this way, but I hold on as I needed to make sure to be able to make new backups.
(In Roon you can NEVER make enough backups at different locations, but that is for another support topic).
@support - I do believe that the ContentNetwork Servers in Roon’s infrastructure are overloaded or need an urgent restart.
Dirk