We have been in our house for several years and through that time we have had problems with a leak. Just recently we decided to put new flooring down and at the same time address the problem. We have bought a new trap/ u bend for under the shower twice and it still seems to be leaking. We have looked at the large nut which is under the shower strainer and the metal screw which is part of the drain. One side seems to have less thread than the rest. Could this be the reason why we can't get a proper seal? If not what do you advice? We are desperate as it has now been a week with out a shower

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