Full disclaimer I have no experience owning or managing a business. My mother is in her first year of owning a small nail salon and doesn't speak English well so I am trying to help her out. A customer recently contacted us saying she was overcharged $100 (she said her total was $42 but she says we charged $142). She sent over a bank statement that "proves" it. However, we looked back at our records and found the receipt with her name on it and the day she came in and we charged her the correct amount ($46.50 for services and $3.50 for tip).
How we should we go about this? What should we tell the customer? Can we contact her bank? Sorry if these questions are amateur hour. I am just not sure of how I can help my mom here.