<human>:  What is the best method for removing a set-in stain from a carpet?
<bot>: The best method for removing a set-in stain from a carpet is to use an enzyme-based stain remover. This type of cleaner targets the proteins in the stain and helps to break them down, allowing the carpet to be cleaned much more easily than with conventional carpet cleaners. It is also important to thoroughly rinse the area after using the enzyme cleaner, as residues can cause further staining.