Power BI Report refrershes failing with Timeout Error using Data Gateway.

Initially we thought issue was related to some networks firewall rules running on the background for One of the Gateway server.

We have 2 server cluster Gateway and in one of them the netwok traffic rule was blocking the outbound traffic on port 80. and that was causing the issue. we worked with our Network team to remove the rule. after that for few days the Gateway worked fine.
BUt again from 9th Jan it's having similar refresh issue. and we checked with netwok team again and they dont see any blocks from firewall.

We are really clueless what is causing this issue. any idea information would be highly appriciated.