All my unassigned tasks vanished overnight

Hi, about 300 of my unassigned tasks -those not on lists- vanished overnight. All of them.

My tasks on lists seem to be all there.

The previous day, I was doing cleaning on that list, since the android app stopped synching, and it was sluggish before that. I had over 50000 completed tasks on that list. I moved those 300 uncomplete tasks to a temporary list, deleted all completed tasks, then moved those 300 back, and deleted the temprorary list.

I most definitely did not delete those 300 tasks in question, and I checked hours before going to bed and going to bed that on my phone, in the desktop app and in my desktop browser they were all present and in synch, and addings tasks was very snappy and synched across devices.

Official chat was completely useless and I couldn't even reach or be connected to anybody in the correct department after banging my head against a wall for an hour.

I have little hope of fixing this, but is there anything I can do, or should I just finally bail out of using this buggy mess of a software?

Thanks