I bought my latest Shield yesterday and have a problem with the slide lock. Field stripped it for initial cleaning before shooting. Also own an M&P 9c but slide lock is different setup. When tried to reassembly after cleaning and lube I was unable to get the slide lock up. I am certain that recoil spring assembly is in correctly. When I look at the slide lock from the side the rear most tab sticking up is hitting the slide without any cut out designed to relieve it. It would appear that the tab is misaligned as it prevents the stop from rising up to lock the slide. Any input or opinions would be appreciated. Intend to call S&W tomorrow if I can't figure it out. TIA