Stop with follow/unfollow and work on growing your page authentically before you start posting ads. You need your followers to be fans before they will buy your stuff - especially if they're buying stuff they're supposed to wear. If you have an authentic following it will also help you avoid getting arbitrarily banned in future. Take a look at facebook pages like doggo bamboozle army or african wild pupper (doggo?) they are facebook pages, but they started out sharing doge memes, got the community engaged sharing pics of their own dogs and memes, and then started selling t-shirts and merch once their followers actually wanted to rep their page.