(FR) JJ - pair vs river bet

I think overall is ok.
Pre 3bet is the right play. Your hand is very strong against the BTN range.
Flop's good. Cbet 1/2 is ok for me. Value and protection. His calling range IP against BB is pretty wide too.
Lower PPs call this IP often. Ax calls too.
Turn pairs. He has A2 and 22 in his range but that's it. It doesn't change much in fact. If he had a set already, 22 becomes unlikely given the new blocker. That leaves us 77 and TT.
That said I like the bet. I think you can play this has a check-call against his floating range, but forget that here.
Your 3bet range against BTN shouldn't be extremely wide and will mostly contain strong broadways, some PP, Ax's.
You 3bet and double barrel, so you don't have Ax often imo. You have a strong PP or a set most of the time.
That said, I think mostly A♥: will float here. It's 1/2 bet, he has position and odds for the flush, so would call instead of raising?
River comes the scare card. I think check is the standard play. The 3rd barrel would look very strong and not consistent with Ax imo. You won't get called by many worse hands, including aces that hit OTR. You have SD value, so don't turn your hand into a bluff.
On the other hand, if you check, some Ax will bet. Some missed hands will bluff too. So check-call may me good against small bets. Against a PSB just fold with no info.

Preflop sizing is too small. Make it at least 12BB in BB, you have polarized range here. Flop is fine. Turn is fine. River is very close imo. A2 is massively blocked now, as well as AT, A7. He has basically a FH here. That being said, we still have some AK ourselves, so those might make a better call than JJ with a heart. Overall I agree with folding.