From the test results I attached, my colleagues from Philippines couldn’t access the site if the domain is Proxied to UpCloud but no problem with Proxied to other server such as Vodien.
I find that non-proxied to Upcloud no issue too.
All these results are test on Philippines. So far no problem accessing from Singapore and Malaysia.
The Ray ID: 572144d15b9bf5ad (Accessing from Philippines to UpCloud xx.232 Proxied)
I know that error 522 is unable to reach web server but the site is reachable without proxied from the same web server. So this is not unreachable issue. This is weird.