I live in Florida have pvc pipe with male threaded end where the submersible is screwed on to pipe . Pump came off pipe was able to recover. Can't keep on on pipe , we replaced male end, old one was damaged used teflon tape got as tight as we could still came off again. Should we glue it?

Greetings from Sarasota,
should we glue it?This is a male PVC threaded adapter you're screwing into metal female threads on the pump isn't it? If so the answeris no. The glue won't bond.
Sounds like the problem's in the female threads in the pump. Have you contacted the manufacture about this. What do they say? Perhaps they could furnish a new part or give you some idea of what you can do. If you haven't contacted them I would do so at once. Let me know what they say. Good luck, Tom