I‘ve accidentally bought 120 Wolfgang Cells for 325 gems.
I wanted to buy R-Cells instead.
I asked if they could add 290 gems to my account so I would just buy 20 cells.
I would place in Wolfgang in a habit and then send a picture before and after selling. If it‘s needed, I will even rank up him so it can be controlled in the profile

Balance and proof

@stein contact in-game support, send them the screenshots and ask nicely for a full refund of your purchase. They will probably knock you back the first time, just raise another ticket, be nice but firm that you bought these accidentally and you might be lucky and get them reimbursed. Getting support to help is a bit like trying to squeeze blood from a stone - viel Glück

I‘ve already asked two times but they don‘t want to give my gems back, they just tell me to active purchase warning.

@stein keep asking, say that you were not aware of the purchase warning and thanks for pointing this out, however, that doesn't undo what happened, so please.....

....just keep raising tickets and pray!

@stein you should have enabled the the 20 gems warning, I hope you did and like David said maybe you wear them out