CloudFlare blocks external post requests?

Question

cloudflare

Hello!
A payment system is connected to the site, it returns a post request about the status of the payment. The script on the site accepts a post request and processes the data. Everything worked for 3 years without problems. But recently, post requests stopped reaching the script. In the logs of the payment "Error The operation has timed out".
I already added a rule to the script with disabling protection and added the ip of the payment system to the clodflare whitelist. No use, stopped working. But when I pause cloudflare, everything works with a bang.
Tell me, can anyone know how to solve the problem. Cloudflare support contacts not found

Answer 1

the easiest way is to send directly to the IP, the second option is to proxy through the third IP
, everything else is unreliable, because xs where in anti-ddos scripts can stumble