Bug? Projects are randomly changing to another project by themselves

Really hope someone can help me out. I’ve been using iOS OF3 iPhone and I encountered a really strnage / serious bug / problem.

Hundreds of my actions in certain projects were automatically defaulting to a different random project.

I spent a long time selecting all of these individual actions (there needs to be a select all button!) and then changing the projects back to the correct one. But on a clean up they automatically changed back to the other random project again !

After an hour of racking my brain and trying everything I could think of I left it. Next day I opened OmniFocus, tried changing the projects to he correct ones again, and this time they stayed and did not change to another project by themselves.

Anyone know what was going on in case it happens again ?