The lovely new kitchen is only a month old. We cooked pancakes this morning and now have his stubborn mark on the glass under where the pan was. It feels like there is someho g there but it's almost completely flush with the glass. I have tried Hg grease away, fairy power spray, a glass microfibres cloth, hot water and fairy, nothing is shifting it. Is it irreparable? Feeling very depressed about it!have attached a pic. Any ideas?