Drywall + Mold

Hello dear craftsmen and craftswomen,

Two years ago I covered the walls of the rooms in my (at that time still) unrenovated house with drywall. Of course, I dried out and primed the walls beforehand.
Now it seems that moisture has gotten back into the walls and mold is starting to form on the backside of the drywall.

Are there any methods or ways to save me from having to renovate everything from scratch again?

If you cover damp walls with dry drywall sheets without fixing the cause of the moisture, are you surprised that everything is molding again now? Without a professional who looks at it on site, you will probably have to redo it again and again. No one can see into the future here, what is going on with your walls :)