The bag loose after 15 days

At this point based on your description of the meat being dry and the bag is loose it wouldn’t adhere to a new bag anyway, so don’t bother wasting a new bag, nor your time trying. I’m curious though, where did you buy the meat? I mean from a butchers’s display window? If so then the meat was dry to start with and adhering would be very unlikely. We recommend ONLY buying sub-primals that are still sealed in cryovac material. Then the direct transfer would have included the proper moisture for successful adhesion.
Ron