It may be pre pasted which i believe still calls for paste? Or if you cleaned the wall first, which is proper prep, there may still be cleaner or what ever you used on the wall and or if there is texture on the wall then the paper won’t stay and grip or be a smooth application. Just suggestions off top of my head.

Where did you buy it and what steps did you do?

My wallpaper guy is having same problem. Were u able to resolve this?