A couple of things to remember about breach plugs:

Always use some sort of quailty lube made for threaded applications, I use antiseize and love it.

Never over tighten your breach plug, finger tight is plenty. If you tighten much over this it will probably stick and could overstress the threads.

Some shooters will loosen and re-snug it every 10 or so shots if it is prone to sticking. I have not had that problem since I started using antiseize.Evenafter shooting dozens of rounds I can usually remove the plug with slightly more than finger pressure.

I hope you enjoy this bug you've caught, I know I do.