FPS drop and very high frame rate

PC spec:
Windows 10
Intel i5 4460
16GB RAM
NVIDIA GTX 960

Im having performance issues while playing any type of content in this game, my fps drops 5-15fps and my frame time rise up to 1500-2000ms. This happens everytime I go to fast in a map, while some boss abilities, I kill to many mobs or simply just playing the game.
I tried lot of things and saw many videos trying to fix this problem (I also did change the sound settings in production_Config.ini to false) and nothing change to me.
I dont know what I need to do to play this game smoothly.
Here I put an example image of the issue (upper right):

Same here when I enter a contract or map the fps drop to 0 for 1 sec and it goes up to 200 after. Ive verified the game cache, set the indesirable soud to ''false'' update and optimize my nvidia driver and I even put the game on my nvme but still got fps issues