Pressure Relief Valve on top of filter is leaking. What to replace?

[Esand323]

My sand filter (Hayward S210S) has a relief valve on top that is leaking. It's not leaking where the gauge screws into the valve, but between the filter and the valve itself. The valve just continues to spin when I screw it into the filter. Is it possible that I'm missing an o-ring? I also put a bunch of teflon tape on too, but that didn't really help (came off in the photo).

Should I replace the valve and the top of the filter (not sure what is called). Thanks!

Here is where it screws into the filter. Missing o-ring here?

 

[PoolStored]

Yes, there is an o-ring for that filter.

SX200Z5 O-RING, 13/16” O.D.

If it is spinning, then you either need to replace the relief valve or the SX244K Top Closure Dome, as one, the other, or both are stripped.