Can you post a photo?
Many slides do not close 'flush' as there is a rubber seal/gasket that gets squeezed between the slide itself and exterior wall that provides the sealing when the slide is closed. Depending on the thickness of the seal, the slide may stick out a tiny bit.
2016 Flagstaff 8529IKBS Diamond Package 5th Wheel-Goodyear Endurance Tires
2017 Ford F-Series SCREW 4x4 - Factory Puck B&W Companion
TST Tire Monitor w/Repeater - Sinemate 3500w Gen.
Days Camped: '18=51 ☼ '19=58 ☼ '20=110 ☼ '21=21