Retrax tonneau cover issue

I recently purchased and installed a retrax tonneau cover for 2013 tacoma crew cab and have found that the weather stripping on the end that come over my tail gate does not yuch the top of it. I called the manufacturer and was told that my year tacoma the tailgate is not flush with the sides of the truck it drops down about a quarter of an inch. anyone have any suggestions on how i can raise up my tailgate or any idea to seal this as i get water in when it rains.

 

Just go to the auto/ hardware store and get some door seal material (comes in a roll). Clean the tailgate top with alcohol to get rid of any oil, that way the adhesive strip sticks nicely.

just make sure you get it thick enough to close the gap.