Repairing Bubbles in Rug Flooring?

A friend of mine who does all my floor covering for me and does it for a living, uses a small thin sharp object to prick a few small holes in the bubble, to release the air. This works sometimes if it is not a large area. If the covering is not glued you may be able to pull a portion of the rug back starting at the edge till you get to the affected area. Use something smooth and heavy to work the bubble out by working outward toward the edge. If this was put down by a professional recently have them come out and correct the problem. I hope this helps you. When I said something heavy i meant something like a heavy smooth piece of pipe.