I am replacing an old tub with a new tub and drain assembly. The assembly will not align with the drain and tub. How do I fix this?

Describe where the alignment is off and maybe I can tell you what needs to be done.

How far is it off? If it's less then a inch perhaps you can nudge the trap over. We need more details before we can answer.

They make a offset tub waste, (see image) that just might solve your problem.
Good luck, Tom

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