You got to keep the seals treated with some type of seal treatment. this may have to happen a few times a year.
Next, clean the slide roof and top of wall that touches the seal. I use a cleaner called namptha. I get it at Lowes.
https://www.lowes.com/pd/Jasco-32-fl...tha/1000147043
Wash it and treat it with a product call Rejex. A waxless polymer finish. Most any polymer finish will work.
RejeX: Nothing sticks but the shine!
Again, treat a few times a year and the seal should not stick and rip.