You will have to contact email@example.com or tag @administrators here or the moderator on the Discord server for help. Make sure you have the account names and purchase dates, etc. available for them to be able to help.
This is happening to me as well. Possible to clear? Thanks!
@wtowne89 This often happens when there has been an update and players have different versions of the game. Did you check for that?
" it makes me fear that I invested my money with the wrong developpers. "
You are absolutely right !