I have been using Greenpro for a few years now to clean our dryer duct. We had an issue back in 12/18 that our old dryer was not drying anymore. We had a cleaning done at that time from Greenpro but it did not solve our problem so we purchased a new dryer. The new dryer was working fine but we were getting an error code that there was an 80% blockage. We called PC Richards which we had a service contract with for the new dryer and they determined the problem was not the dryer. We called Greenpro and even though 5 to 6 months has passed since our cleaning they said they would come look at it no charge. Greenpro had to go into our attic of our Condo which is not an easy task and cleaned our duct from the roof end of the duct. There was a blockage and Greenpro cleared it and now we do not get the error code anymore. Greenpro did the right thing by us and found the blockage so we can sleep at night. I highly recommend them.