In the online store to validate the callback endpoint created by the payment methods plugin we are getting an error 500 in the request that shows us (see attachment) a Cloudflare error "Error 1101
Worker threw exception "
I send again another attachment with the data of the request that we are making, just as the endpoint is visible in the screenshot.
As this is related to endpoint validation, we were only able to test it through the payment methods platform, which I cannot give you access permissions because it has a double factor of authentication.
Then it’s quite likely that the Siteground Worker (sg_worker?) isn’t compatible. I think there’s a way to remove the SiteGround Optimization Worker from your SG dashboard.