Shopify checkout and getting this error message when I put in credit care information: "We are unable to complete your payment right now. You might want to retry or to try another payment method."
If you open the transaction you see in the timeline more details why we were not able to show you the different payment methods. I just opened some of yours and I see that the access credentials are not correct. Please verify that you have setup your Processor correctly.
See the screenshot below for more infos.