Transmission pan leak

I have a steady drip on my trans pan I just dropped and replaced the gasket and filter. I used a lube locker gasket no cheap one and its still leaking. I drove the car around today to heat it up let it cool drove it some more let it cool still leaking. What gives? Do I need to use rtv? I tighten the bolts to 12.5 lbs or 150 inch which is what i read it called for.
BUy a cast aluminum pan. They have a super thick machined pan rail.
It will not leak no matter the gasket. I don't used stamped metal pans for anything anymore. Differential, valve covers and trans pan
are all cast and never leak.