i just started using this app 4 days ago. Today i realized that my mastery stars on the profile suddenly disappear/reset by itself (?), although up to yesterday it had been approximately 1k stars. The percentage of the mastery progress of all items (vocab, grammar, kanji) on the stats tab is gone as well. All of them turn into 0%
I’d wait a day or two to see if it resolves itself. Statistics on renshuu are sometimes delayed, and lately there seem to be a lot of caching issues as Michael sorts out the new content distribution network.
In particular, I’d suggest doing your normal studying, and seeing if the updates don’t appear.
