Having followed the posts on one step, thought I would give it a try tonight. Bonnet buffed some long corridors, first thought was this is good stuff, carpets do look brighter. When I walked back over the job at the end complete horror, corridors looked liked zebra crossings. One strip perfectly clean next one dull. I thought at first it was the way the pile was laying but it was not. Bonnet buffed many times before but never had this problem. What has gone wrong please.