Which flower is having the trouble? Was it the first to open or has it only just opened? Also, was the plant blooming when you got it?
If it was the first to open, it could be finished blooming. If it's only just opened, it could be blasting. That's a term we use when a bud or flower reacts (negatively) to a suddent change of conditions. It gets that shriveled look and goes all limp. I've had a few blast immediately after purchase. They clearly were used to a different environment. It doesn't hurt the plant. Just the effected buds/flowers. I've found that buds either just about to open, or newly opened are the most vulnerable to blasting.
Nothing you can do in either case.