Liquid Metal Peace Motion Lamp Flow Problem

[Trevi]

Hi there, my first post. Bought a Liquid Metal Peace Motion lamp for my daughter this Xmas. It worked beautifully till about a week ago when the flow just became sluggish and the wax just seems to gather along one side of the glass and doesn't float. Any ideas on how to get it working again?
I've read that this problem can be caused by cold weather but it's summer here and the lamp I have since bought for myself (same make) works like a charm.

[Trevi]

Thanks for the advice. I'm really considering doing that. It's such a pity because they're beautiful lamps.
Thanks again though