J9 s on button flops flush draw faces raise?

why did you 3bet AI flop?what were your reasons for doing that?

You need the pot to be paying you about 2:1 to break even calling flush draws all day long, assuming your flush always wins when you hit it.

This pot was only paying you about even money, since you had no fold equity at the point you shoved over his raise, and there wasn't much in the pot to start with, so for all practical purposes you were getting paid 1:1 odds. Not near enough to call a flush draw, especially one which may not be the best flush.

Fold here every time the pot is not more than twice what you have to call to see 2 cards. Remember also that if it's not a shove, you will have to pay again at the turn to see the river unless you hit the turn. 2:1 odds are needed with 2 cards still to come, with one card you need about 4:1

By the way, and I am not adding this to encourage loose calling, but the fact you had 2 overcards to the board _may_ have given you better opportunities to win the hand since you can also hit those, but they must be live cards - ie. your opponent doesn't either have better overcards, a better pair than your overcards or a hand that dominates your overcards by having one of them with a better kicker.

AKs here for example with the flush draw is a marginal call maybe, since you have a 54% chance to hit either the flush or an A or K by the river.