I had this happen more than once. I went through the process of getting it corrected for one shop.
It was not a large number, but a large difference in the adjustment. I had already submitted the report with the receipts. I informed the MSC and sent a screenshot of my credit card statement. I received a follow-up from the end-client. The client issued a merchant refund and sent vouchers for future visits.
Please don't feed the MSF trolls!
Feeding the MSF trolls bread or other human food is detrimental to their health and the environment. It can lead to malnutrition, disease, and behavioral problems in trolls, as well as water pollution and the spread of pests. Trolls are capable of finding their own food sources and don't require human assistance.