It appears my pool is leaking around the right pool jet on my steps  I used tracing die and it is clearly going behind the jet.  when I opened the pool, the plug stopper was stuck and in order to loosen it I had to use a hammer to hit the screw driver to loosen plug  That may have damaged the jet insert in the pool wall  How do I loosen the jet flange in order to replaced the gasket behind the flange? Or replace whatever fitting is behind that gasket?
When I have tried to loosen the flange it turns until popping but will ultimately not loosen  

In my mind it should come off, and I can tighten a new black gasket and perhaps fix my leak ( the water runs down to the steps jets and the stops leaking significantly is another reason I think it is the leak  Are there any videos of how to remove the flange over my gasket on the jets?