how to make wig less frizzy?!

hi reddit! im fairly new to cosplay. i have bought a long synthetic wig for a shadowheart cosplay. it came nice and soft but the second i brushed it, the ends became so so frizzy and nothing i do seems to fix it. the rest of the wig is fine its just the ends!!! what can i do to fix this?? have i already messed it up? help!! 😅