Fold a white tea towel and place over the residue and then the iron on top. Apply short bursts of steam to the hardened residue, then re-scrape the loosened residue with the blunt knife.
Most stains can be removed from fabrics, upholstery and carpets by a good professional. Unfortunately, these incidents are hard to predict how long it will take to eradicate the spills. The list of stains that can be removed are exhaustible, but here are a few examples of what a professional can remove.
Oil and Grease.
Cosmetics and Nail Varnish.
Adhesive and Paint.
Most Food and Beverages.
When requesting this type of service for a professional upholstery cleaning company of carpet cleaning company try and include the stain removal with something else that needs to be cleaned when possible.