FWIW - WD40 is not a lubricant - it’s a penetrant.
You might want to search the board, I think others on here have had a similar issue and posted ways to correct it.
They may have also indicated the type of lubricant they use for the mechanism. My first thoughts would be dry silicone spray. It works well on most all similar automotive mechanisms.
‘91 Ultrastar Champion‘02 Georgie Boy Landau 8.1l Workhorse
‘03 Jeep Wrangler TJ 2018 Jeep Wrangler JK toad