Won roll but did not recieve item?

I just killed mutanus the devourer with a group and he dropped mutant scale breastplate and i needed it and everyone else greeded it but nothing ever happened! with the roll. as soon as he died everyone pretty much left the group except me, i have pictures of the rolls in the chat too. i want my fricken brestaplate! im so angry. i clearly won it, everyone else greeded or didnt vote, being the only one who wore mail, i needed and won so why dont i have it!