Broadline is not a good product!

Bought broadline top spot for my cat. Vet told me not to bath my cat after applying. Have to apply every 6 weeks! Followed the instructions exactly as told! And still struggling with fleas!!!! Its her second treatment now but yet she still have fleas!. She's a indoor cat. Got into contact with a stray cat that we took care of till he got a owner. Had to get pest control to spray house. The vet didnt have flea pills only broadline or collars. After 2 treatments still no results!!Broadline doesn't work!