Nice gun. I'm assuming that the bolt moves when you shot, but not enough to fully cycle the gun. If this is the case: Is it enough to cause the first round to fully eject, or (1) does the bolt close (or partially close) on the spent hull? Or, (2) the spent hull is ejected from the gun and the bolt closed on an empty chamber. Or, (3) does the bolt stay open after you shoot? It's hard to tell you what's wrong without having a complete description of the problem. Also, you've not told us if this is something new. If yes, than what precipitated the change? Typically, 1100s start acting up right after you've had them apart for cleaning or you changed ammo -- you didn't tell us what ammo you're using.
Unless something is broken/worn, or you've switched to too light loads, the number one cause of 1100 troubles is getting the rings re-installed incorrectly. Also, the rings and mag tube need to be clean enough so the rings slide freely as the gun it turned end over end with the bolt open. If the mag tube is rusty, it needs to be polished. (Mag tube corrosion is a common 1100 problem, and it's why the model 11-87 switched to stainless steel.) A worn O-ring is also on the list of typical culprits -- they are cheap, install a new one. Next, clean the gas ports, many otherwise clean 1100s have crud in the gas ports. The Skeet B 1100 has two 0.086-inch vent holes, use a #44 drill, or specialized crud punch, to clean the barrel vents.
These days, with the proliferation of "lite" and "extra lite" target loads, some ammo just isn't powerful enough to fully cycle an 1100 even if everything else is okay. You might try some name-brand 12-ga 3-dram 1-1/8-oz 1,200-fps standard target loads (not discount store promotional field loads). If the gun functions properly with these, then you know there's probably nothing wrong. If you are going to feed your gun a steady diet of light loads, then you might consider having the barrel vents enlarging by someone who knows what he's doing.