I seem to have a lot of trouble in 3bet pots. Comments on play all around are appreciated.

Hand 1:
UTG is a loose aggressive player preflop, fairly passive postflop. Button is loose passive preflop, semi-loose/semi-passive postflop. Everyone has stacks right around $200

Hero is SB with AcKh
UTG raises to 10, MP3 calls, CO calls, Button calls, Hero raises to $50, UTG folds, MP3 folds, CO folds, Button calls

Flop Js9s7h (Pot: $140)

Hero checks, button checks

Turn: 2d
Hero checks, button bets $50, Hero?

Hand 2:
CO is a pretty good tight/agg player who raises a wide range in late position, Button is same Villain as last hand. Hero has $260, Both players cover. An orbit or two ago, CO raised, got 3bet and 4bet pushed with AA.

Hero is SB with JdJh

Folded to CO who raises to $10, button calls, Hero raises to $40, CO calls, Button folds

Flop (Pot: $90) 4s5d6h
Hero bets $50, Villain shoves

Hand 1, c/f. His calling range pf beats you.

Hand 2, call. You're ahead of him much of the time. He thinks you have AK.

What Venice says.

This call seems super thin with JJ

i think hand 1 we should probably shove flop? put opponent to a decision.
as played i think fold now.

hand 2 its definitely close. i guess sigh call and hope he shows up with 9's or 10's more often than q's

Preflop shove.
Turn call.

I avoid 3bets from the blinds. Especially w/AK or JJ, both difficult hands to play OOP. I will 3bet QQ+ of course.

If I have good reads and good image this can change, or as a squeeze w/mult limpers who all look weak.

Hand 1: This is a good spot, but I would raise a bit more. There is $40 in pot, I would bet ~100 and shove flop or even shove now. As played I shove flop.

Hand 2: I don't 3bet preflop here, just call and play poker, especially 130BB deep for you and more for 2 villains. As played, you're in a tough spot. I don't like calling allin this deep on flop w/JJ. I fold against "pretty good tight/agg player" here, can depend on my image tho.