Double charged?

I was assisted by one cashier, and I reached my spending limit, but she didn't inform me about it. I believe it should have been visible on the receipt. Regardless, I continued with the scan payment, and it went through. However, they refused to give me my medication. The cashier then directed me to the next cashier, who informed me that I had reached my limit. I changed my limit, tapped again, and the payment went through. However, they charged me twice, despite being told that the 'scan to pay' would be a reverse transaction.

PS. All cashiers should be properly trained on how to review payment slips so they can assist customers effectively. This would help prevent situations where they are caught off guard and unaware of the actual issue with a transaction. Proper training would ensure that customers receive the help they need in a timely and efficient manner.