mishandle

verbs

make a mess of, destroy or ruin
"I botched the dinner and we had to eat out"; "the pianist screwed up the difficult passage in the second movement"
ball up, blow, bobble, bodge, bollix, bollix up, bollocks, bollocks up, botch, botch up, bumble, bungle, flub, fluff, foul up, fuck up, fumble, louse up, mess up, mishandle, muck up, muff, screw up, spoil
manage badly or incompetently
"The funds were mismanaged"
misconduct, mishandle, mismanage