First check the bearings - a lot of times dirt gets inside even if you clean the surface, and that slows down the rotation. If you see them oxidized or with salt residue (if you fish in saltwater), they probably need specific reel lubricant like silicone oil or light grease, not just whatever you have around the house. Before taking it in for repair, carefully pop off the side plates, clean the bearings thoroughly with a dry cloth, and apply a tiny drop of lubricant; sometimes that fixes it. If it's still stiff after that, then it's time to see a technician, because there could be a damaged bearing or the shaft could be misaligned.