You can check yourAbandoned checkoutsfor your order attempt to see if there's an error message that will explain the issue further. To do this, you can follow the instructions below:
On your Shopify admin, go toOrders > Abandoned checkouts
Select your order, then scroll down to the order's History section and click on the line items to expand more information
Check for an error code in regards to the failed payment attempt
If you've located an error code but aren't sure of what it means, you can reach out to our internal support team so that we can help clarify the error code for you. We aren't able to do this via the Community Forums at this stage, but you can reach out to our support teamvia our help centre here. Once you've logged in to your store on our help centre, type in your question or the topic you need help with. After that, you should see theGet Supportheading at the very bottom of the page, and you can clickContinueto start a support request. From there, our support team can assist you further.
Are you currently testing your store's checkout and payment gateway? If you are, feel free to go through the documents below to help you place a test order on your store:
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