I get frustrated when I burn candles & all the wax doesn't burn. I found two ways to deal with this & to continue enjoying them.
I have a hot plate that I used at work to keep my tea hot that I can put the jar on to melt the wax. If there's a lot of wax I keep doing this to release the smell.
The other thing I've found is to use an empty plastic tart holder & refill it with the melted wax. Then I can break off whatever I want & put it in my tart warmer.