I need help, high ping only in Rust.

Hi all, i play rust since legacy and never had problems.
But now are 2 weeks i can’t play because i have a HUGE ping problem.
I lag only with this game, tryed other games and no problem.

When i do Battle royale my ping is 4.000-6.000
When i play survival mode (official server only) my ping is 4.000-6.000

Sometimes i play good with 60 ping but when i meet someone or some building my ping go again to 4.000-6.000

I play with 5 friends and i am the only one who have this problem

My pc is:

Windows 8.1 64 bit
intel core i5-4460 CPU @3.20 GHz
16 GB RAM
Nvidia GeForce GTX 970

Is NOT fps problem, but a PING problem, some one help me please im desperate! HELP!!!