So my pc runs Minecraft at around 40-70 fps (with medium setting)

and my Minecraft runs at 60-128 fps with optifine.

So after like, 10-15 min of playing the game suddenly freezes and my fps goes down to 0 (the memory percent isn't above 40%)

Tried everything including Task manager>details>priority high

even set the memory to half of my PC memory

but it still freezes after 10-15 min of playing even tho I get high fps.