I see you have the Killer network system Vishiz. Try some of the solutions found on this thread:
i didnt have any of the software installed for it as it was, and installing it and then turning off the advanced stream detect didnāt seem to do anything. neither did any combination of adjustments through the control center.
In game on the Menu > System > Network. Experiment with āUse IPv6 when availableā and āOptimize network for speedā. Toggle those on and off.
Iāll link the Blizzard Latency support page here for you to work through:
Expand the āAdvanced Troubleshootingā section as well.
those were the first steps i took
Sorry - I missed that I had you work through that. Iām running out of ideas here Vishiz. You might open a ticket on this. Get a fresh set of eyes.
https://us.battle.net/support/en/help/product/wow/197/1462/channels
I would refer to this forum thread so the Tech knows what you have tried.