Yesterday a customer was paying his invoice at my shop and I used the chip/swipe reader along with an ipad 7 that has always worked fine, and I got the message "reading card", then "payment not processed". It then gave me an option to try again, and I got the same "payment not processed", and a third time. Anyway I went on my site to the invoice, and was manually entering the payment when I saw in the log it had already been paid THREE TIMES. I told the customer I would sort it out and call him when I did. He wasn't overly concerned, but I was.
I called Shopify support to try and cancel the charges, and the guy helping me "escalated" the situation because he couldn't help. I uploaded the logs from the ipad to Shopify. That was 4:30 pm on Tuesday. At 8 am Wednesday I got an email
from the Retail Technical Team at Shopify, my colleague has informed me of the issue that you experienced with Order X
I have reviewed the logs and can see that there were three separate attempts on the card for $738.74, and the logs indicate that a Thank you page was displayed, but I understand that the screen never moved past a 'Payment cannot be processed' message on the POS device. I have sent this information to the developers to review further.
Being dissatisfied, I called Shopify support again, and was unable to talk to anyone who has anything to do with credit card processing. I was finally told that my customer was charged $2216.22 for a 738.74 bill and it had already gone through to his bank. Then I was told to refund the amount overcharged which is the only way at this point as the charges already went through. I did, and now my sales for today include -$1477.48. I am currently trying to get someone to take that off of my totals, as it makes all of my accounting inaccurate. I think the person I talked to is "escalating" it to someone else???
Anyway I am not writing this to talk bad of shopify or start any drama. I am only suggesting that if you are running a credit card on your POS and get a message that the "payment cannot be processed", check the log under the invoice on your back end website before running it again.
I now have a customer that will have five transactions on his credit card statement, three charges and two refunds. Needless to say it looks very unprofessional. This never happened in the last 10 years of processing cards with a terminal before using Shopify. I am only providing this information in case in can help someone else.