Did you "clear coat" them with either a Testors acrylic or a Future mix?
If not, depending on the decals, it may not be too late to save them.
I have clear coated after I had some start to peel, and it worked for them.
First you carefully brush them back down with a soft bristle paint brush and warm water.
If they are of fairly good thickness, you might then also try "snuggling" them down next with a decal softening solution you can get at your local hobby store. This will ensure a better adhesion to the model's surface.
Then after they are re-dried, and before they peel again, clear coat them with the finish of your choice.
If one starts to curl while clear coating, carefully working the edge back down with a soft brush before the clear coat fully dries.
Good luck
Tom
Tom T
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