Steam Multiplayer lag every 4-5 seconds (4.27 version)

Hello,
I have been working on Mulpiplayer project but it stuttering in every 4-5 seconds. Somehow ping is increasing sharply in that period. Do you have any advice?My version is 4.26. I tried smooth framerate and changing max substeps but not working.
Thanks

You need to run network profiling to see what’s being sent in those bursts.