It looks like whatever caused that "nick" (dent) raised some metal into the frame rail, causing the slide to stick. I see nothing that can't be solved by a simple file stroke; it won't require a gunsmith. The question is what caused the dent in the first place. It looks a bit like a bad magazine or a magazine button might have hit the frame some way, pushing up the metal. I would try to find the cause since even if the immediate problem is easily fixed, it may recur if the real cause is not corrected.
(BTW, I agree that some lube would help, but its lack is not the cause of the problem.)
Jim