Do you mean a refund, @Artamorada? 

If so, check out the steps to Process Refunds in our Support Center. 

Let us know if you have any other questions.

I just wanted to get a credit for a few dollars they charged my card when we worked with the square.

how do you extend a credit charge, say if someone returns something.

you can issue a refund partial or full to their credit card.

https://squareup.com/help/us/en/article/5060-process-refunds