I used to use Brake & Clutch cleaner like
THIS, (cos I always had it).
Hairspray probably works the same way?
It works like a lube to allow grips to be slid on and positioned, but them evaporates to nothing leaving a secure fit.
I'd take yours off and give them and the bars a good clean, then re-fit with whichever of the above you've got.
[EDIT] the brake cleaner is absolutely superb at cleaning chains, mechs and anything oily