Spot on Skilhunt H300

I just bought a skilhunt h300 with the new inhouse Emitter , it looks good, rosy and powerful, but a spot appeared after 30 mins of use.

The lens bezel should be "finger tight" but I can't seem to open it, I have a lot of tools but nothing will open it, does anyone have any trick?

my only idea is to modify a tool on printables that opens the h150, I will need to make it bigger, but I hope there is another solution