In the chandelry is some WILDLY expensive products: silicon lubracant either in a spary can or a little stick like a lipstick.
But before you thrust you hand into your pocket slip uo the mast
with some cotton ear buds, toothbrush (use your wifes as it tastes horrible afterward) and some slim rages. Try to clean the inside of the track up the mast.
the with the toothbrush clean each of the slugs attached to the mainsial. Sometimes a little gunk in the corners will slow it down, or push it in a direction that they lock.
If that fails then go to the shop and spend lotsa money