I admit to being clumsy when using Google searches, so I'll ask here because I can't find it anywhere else... Here's the issue, we've an area rug in the living room sitting atop berber wall-to-wall. It has developed a hump across its width about mid point. No amount of pulling straight, moving or vacuuming will make the hump lie flat. After a small amount of traffic the thing is back. Needless to say the hump is a trip hazard. Any suggestions?