Cannot do Let's encrypt reservation on our server

Hello Team,

we have an issue about the generation of ssl certificates let’s encrypt for the domains of our clients hosted under our server, the solution used is plesk under linux ,

By tracing the route we have the below : ssl1 is the plesk linux with issue and ssl0 plesk linux server with no issues ,

We highly suspect that there is a block from the internet side in Cloudflare ,

Could anyone please check our server IP whether is blacklisted or not authorized by the DDOS ?

Server IP :

Appending your reply