Can't Lock the Crown on Dynamic Automatic

Hi, I would appreciate advice on how to fix this problem. After adjusting the time and date, I am now unable to lock the crown. This got progressively worse from needing care to catch the thread to now no thread engagement at all. Is this an issue with the case, the winder stem or the crown itself? Is it a job for a good jeweler or does it need an Omega repair? Omega Calibre 1108 Automatic Movement. Model Reference 5200.50.00. Produced 1997. Thanks for advice.

Thanks for the rapid reply. I can envisage the female thread in the crown but don't (yet) understand where the male thread is located and whether it can be replaced. Your comment "watchmaker with an Omega parts account" is very helpful. I'll research where is the nearest one to me.