Why is there an error when taking a large payment?

If you are taking a large payment from a bookers/guest card and get the following error:

This means that the bank has declined the payment. It sometimes happens when you are trying to process a large payment. You would need to ask the guest to check with their bank as sometimes the bank will automatically decline a large payment for security reasons. This can easily be rectified by the guest contacting their bank and making them aware that a large payment is going to be processed.