I would like to hear what type of cleaning method was used as well as what products they used. Also, what condition was the carpet in before cleaning? IF you did get ripped off, the company may have used a product that makes the carpet appear cleaner instead of actually removing stains, or they used in ineffective cleaning method. Another possibility is that the stains have sunk through the carpet and permeated the padding and subfloor. Though the carpet surface appears clean, as you walk on the carpet and as it sits over time you can pull those stains up from the subfloor and padding back to the surface of the carpet. If this is the case, continual cleanings will not do the trick. You need to pull back the carpet and get to the subfloor to correct the problem. You will likely need to replace the padding.