Order had to be canceled, how much should I expect to get?

This morning, I had a 2 order shopping trip and my barcode wouldn't scan at the end. Yesterday this was because I couldn't find a substitution (I could, but none were accepted by the app). Eventually the barcode scanned yesterday, but not today. I went through all of the troubleshooting steps from yesterday and support ultimately had to cancel the order. They then said I needed to return all of the items by hand without the shopping map. I attempted to return the items, but a supervisor told me to bring the cart to the front and offload it on to their staff, which the staff wasn't happy about obviously.

I asked support before I got off the phone what % to expect from the order and they didn't answer but said I can appeal if it is too low. Is there a minimum I should accept? As in, how much is actually fair?

Context: A had 12 items, B had 30, it took about 30 min to shop but the ordeal took an hour. The order was $26.