Peplink 580 problem with accessing http site

I’m having time out and auto log out issue accessing one http site with Chrome browser, but Firefox is working fine. (Firmware version 6.3.1 build 1631)
But on the other Peplink, the same http is having issue with Firefox and Chrome is working fine. (Firmware version 6.2.2 build 1486)
There was no issue before Peplink in the network.

Any idea for resolution?

Thanks

This sounds weird, could you open a support ticket so the team can follow up with you?