These tracks are dirt magnets.
Recommend you take a stiff tooth brush and scrub out the track. Vacuum out the debris. Soap and water may assist your toothbrush. Inspect the track and ensure rubber molding has not broken or slipped out of place. Make sure the aluminum track has not been bent. If so, it's aluminum, straighten it with pliers or tool of choice.
When clean and dry, dry lube the track. My new favorite lubes are 3M RV Care. They will be my new favorites until I find a new new favorite.
https://www.walmart.com/ip/3-IN-ONE-...Lube/133406147
You can get 3M RV Care products in Home Depot, Lowes, Ace, Amazon. Cheapest at Walmart.
Fair Winds and Following Seas