Share 'Sticking wax solution?'

I posted about this a while back but the trail has gone a bit cold, so to speak.Just wondered if anyone had any success in finding a ‘hands on’ approach to solving the sticking wax issue that seems to be a quite a common defect on newer Mathmos bottles, since I still have a couple of (non returnable) bottles which have this issue.

Was contemplating re-filling them using a goo/glitter kit, but wi…