Is the bunching in the high traffic areas like doorways and halls if yes carpet is not stretched enough.
Lumpy carpet pad.
If an improper cushion is used under the carpet it could cause the carpet to buckle.
To remove dents in carpet and rugs from heavy furniture place an ice cube on the dent overnight.
Lumps generally occur in carpeting from poor carpet installation severe humidity affecting the carpet adhesive or carpet seams buckling from wear and tear.
As the ice cube melts the fibers will slowly absorb the moisture helping them to return to their original form.
Lumps in a carpet are sometimes the result of the underlying padding.
The bumps may appear when the carpet padding wears down enough to create slack in.
Not only are lumps unattractive and cause eye sores but they are a hazard that causes trips and falls.
In the morning remove the excess water and fluff the fibers with the edge of a spoon.
Over time your carpet can develop lumps bumps and wrinkles that are unattractive and potential tripping hazards.
To prevent this issue the correct underpad must be used under the carpet.
This would occur if the pad was not dense enough to adequately support the carpet and allowed too much flexibility in the carpet.
In any event the the carpet has to move first.
If the carpet moves the pad can move if it wasn t stapled properly causing bunps in the pad and carpet.