I'm setting up a sandbox account integration on a WooCommerce website. When I try to checkout, I get an error saying 'Transaction could not be processed."
When I look at the log, I see this error:
{"status_code":400,"result":"{\"message\":\"400 Bad Request\",\"error\":{\"code\":\"processing_error\",\"message\":\"No valid payment gateway configured for merchant.\"}
How can I resolve this?