I bought 10 metres of R6381X uPVC Gasket to replace gasket that is startin g to crack and fall apart in lots of places on my various doors and windows . The profile of the new gasket matches the gasket currently in my door fra me - the difference being the width of the part that holds the gasket into a narrow channel in the frame. The published and supplied gasket has a widt h of 5mm between the "edges" and the measurement of the currently fitted ga sket is about 5.4 mm. I was able to easily fit the new gasket although it d oesn't feel securelt held. I was guessing the old gasket "spread " over the years. The problem is the new gasket prevents the door closing. I have che cked carefully where the gasket channel turns at the corner of the frame - and it does not seem to protrude. Is it possible that the new gasket is jus t too thick (it doesn't seem to be) or is there a "trick" to fitting new ga sket?