Looks like the bottom one is cross threaded because the down pipe in the background may be too long, hence putting the trap on an angle. If it's fixed at the bottom, I would make sure your plumber shortens it slightly when you get him back.
Yep I think this is at the heart of it. Pipe forces the whole thing to be -very slightly- at an angle
@lemonade started
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Looks like the bottom one is cross threaded because the down pipe in the background may be too long, hence putting the trap on an angle. If it's fixed at the bottom, I would make sure your plumber shortens it slightly when you get him back.