Abyss pit closing bug

ref #3,520,945,323

abyss monsters all gone however will no open the abyss pit to close and finish to get rewards, happened twice on same map 2 seperate abyss pits.

Tried porting out, spamming gas arrow everywhere and running around to try and see if buried monsters were the issue but nothing

Also says "0 monsters left" on map info which tells me they arent even there to kill.

Any helps would be appreciated thanks !