Hi @CrazyCatWinery. It sounds like you are the victim of buyer’s remorse. Sorry to hear that. Ugh.
Anyway, dispute decisions are made by the bank that issued your customer’s card. In most cases, banks are notorious for resolving disputes in favor of their customers rather than in favor or sellers. There’s little that Square or you can do about it, other than what has already been done. In the end, all the customer has to do is claim that one of your employees pressed the 20% button and that they didn’t even see it. It will be your word against theirs since there’s no way to prove that it was their finger (and not yours) that pressed the button.
Having said that, this is a great reason for enabling on-screen signatures for transactions, especially for stores with high-dollar transaction amounts. At least you have something to fall back on, and more proof of the customer’s intent, with that signature. Even that’s not foolproof, though.
I’ll keep a good thought that you prevail in the dispute, anyway!
Unfortunately, based on many previous people's experience I would think the bank will side with their customers. Disputes suck but are part of owning a business in the modern age. The good thing in all this though is that they aren't disputing the whole charge. There are many people that game the system. I'm not sure exactly what options there are in the Square dispute form that you would fill out at https://squareup.com/dashboard/sales/disputes, I have been insanely lucky and had 0 disputes in 117,721 transactions with Square. Even with Signatures I don't think that would make a difference and will only slow down all your transactions for no real benefit.
If it only happens once in a while then I think you just have to learn to let it go and worry about the bigger things to keep your business going and profitable.
