zipper getting stuck but dress fits - help

[Stargazing]

I bought a rather expensive frock the other day for a couple of weddings - the zipper (up the side) kept getting stuck in the store but the assistant was able to pull it up. It fits perfectly but am having real trouble getting it to do up myself. Maybe it just needs a little oil or something but am scared of marking the fabric (silk) - any suggestions?

you could grease the zip with a tiny dab of vaseline. Try doing on the inside of the so if it does get on to the fabric - it's on the inside of the dress.

candle wax but make sure you protect the material

I'd take it back to the shop. Expensive means it should work properly. Side zips are always tricking but it shouldn't stick. Perhaps there's a problem with the way it's been stitched in or the zipper itself.

rub a candle up and down the zip

Yes agree with the pencil idea