I started a new world last week (single player mode) and i was having fun building my base raiding all the spots and getting ready for the deadzones. Only to appear a massive issue.

When i started the world i was at 150+ fps (I59400F + RX 580 OC) and now i can only get about 40 fps max and i havent changed a thing.
When i join other maps like "Russia" for example, i get 170+ fps. Please someone help! I really dont want to lose all my progress :((((((((