Mid-Levequest crash

Title says it all, no error code to display I'm afraid, I'm just in the middle of a levequest could be preparing to take on a mob or just walking into a close-ish range then all of a sudden *Crash* like a pile of China plates suddenly hitting the floor,

My games windowed, half if not all of the setting are dropped to minimal, yes I do meet the minimal requirements.

Any advice or information on this? Thanks in advance.

P.S.
A little off my original case but... does anyone know how the levequest resets work?
because my reset would take 2 day every week, now its like 2 days every second leve reset... Thanks again!

i have this same problem game crashes on leves or when i'm in SP party, can play game all day and don't do leves or SP party and it will never crash, this problem only started after 1.18b. any advice?

Leves reset every 36 hours.

You can check when the reset is either by using the command /clock or check the timers in the menu under Attributes.