Gas BBQ - Won't light

Question

I have a Vermont Castings BBQ and recently switched the propane tanks. THe grill was working fine and now it does not seem to be getting any gas. I hooked up the new tank and turned it on and it won't fire. There is no smell of propane and the starter is not the issue as I also tried lighting it manually. Is it possible the connection is not being made at the tank? Are there gaskets that I need to check for on the tank and connector to make sure it is set up properly? Any help would be greatly appreciated. Thank you.