My upstairs window has started leaking from the top of the frame, where the sealant meets the wall. It started following some heavy rain. I have been up into the attic and cant see any evidence of water coming in. We have a vent on the roof and had a roofer suggest it may be the flashing. But surely if there was an issue with the flashing, water would also be coming into the attic? Someone has come out to look at the window and suggested the heel and toe needed doing, but having googled this it refers to the positioning of the glass rather than the frame. Just not sure what else could be causing the leak. We have recently had our windows and gutters cleaned and wondering if perhaps something was dislodged/moved out of place. But the roofer said the gutters were fine and no cracked tiles. Any suggestions please???