Shower head won’t screw back

I removed the shower head for cleaning it, but now I can't screw it back anymore: the threads won't click into one-another (unless I remove the gasket so that the two ends can get closer to each other, but then of course the head is no use anymore, because the water will flow from the base too). What I tried was pressing the head and the tube together (with the gasket in), but even then, the threads don't reach eachother.

Question: is there some trick to screw it back together, or should I just buy a new one?