GMAlex my char have bugged

hi alex. this is probishop. my char have this problem, kill monster 1 by 1 died, monster no drop, pap spawn then gone, clear zakum hand then 1st body kill body then gone. i use my other char no problem as normal. got drop kill more monster died in 1 time. can u help me solve this problem. hope 2 hear from u soon.

thanks