Use a 4 hour unscented tea light & do not burn for longer than 4 hours. Using an 8 hour tea light may cause poor scent throw & could be a potential fire hazard.
How to clean your dish/ change wax-
To remove the wax from your burner, simply light a tealight under your burner to warm the bottom of the dish, once the dish is warm the wax should just slide right out. Wipe down with some tissue or a cotton pad. Alternatively, light the burner to allow the wax to melt completely & soak the wax up using cotton pads or tissue and wipe away. Once clean, you're then ready to pop a new melt in!