i had a seresto collar on cat, didn’t work, we use a flea comb, ive use diamaceus earth and sprays...I can’t not wash my cat , there is no way ...she’s mean...my question is the collar been off for 2 days, can I use advantage topical on her with the rare spots ? Oh yeah gave her capstar, but she threw up within minutes....also of I put salt down, will it hurt my cats ? Thanks for input