Apologies for the format. The site i use does give me an option for hand history files.

. 01/.02 nl six max.

UTG: $2.68
Cutoff: $4.20
Hero (BTN): $1.89

Hero deal A5s on BTN

Preflop
UTG: Raise ($0.06), fold, CO calls, Hero calls, fold, fold.

Flop:6h 9h 10d.

UTG bets $0.10, CO folds, Hero calls

Turn: 7c

UTG bets (0.20), Hero raises to ($0.80), UTG calls

River: 3h

UTG: jams for $1.78

Preflop i thought about 3 betting but the raise was from UTG which has a pretty narrow range that A5 isnt beating a lot of. So i call.

Flop: villan bets but the board doesnt really hit his range except flush draws and over pairs so i called hoping to take it down later since im in position.

Turn: board runs out 4 to a straight so when the opponent bets half pot i figured he cant have to many combos of 8s. Like what hand raises pre utg with an 8? So i raise to 4x his bet to give him roughly 2.5/1 on a flush draw with one card to come. Should i have tried this and just bet more?

River: flush draw gets there and he jams. Clear fold at this point but i was wondering if anyone else would try to bluff a relatively tight player from what i have seen (no hud though) on that run out. I figured in this hand his range is tbe narrowest it coulf be and i could have all kinds of hands like 78 88 10 8 maybe j8s or 68s. So i figured if im ever goinf to bluff someone using my range it would best to be here. I had position amd a range advamtage but it didnt work. Any words of advice?

Buy in full. fold pre u pretty much answered why this isn't a good flat pre yourself with your reasoning for not 3betting. Fwiw your 3bet pre would be a bluff anyway so it's designed to fold better hands with regards to your statement about A5 not beating a lot of utg narrow range .

Seems like you're misunderstanding several basic concepts, I suggest the memorable threats on this forum, take advantage of that free and valuable info

Ace-rag suited is nigh-on useless without at least a backdoor flush draw, lower cards, or hitting two pairs on the flop. That is why is it considered a speculative hand - you invest low to hit a potentially strong hand. I don't hate your call OTB, but even if you hit an Ace on the flop, you aim for pot control while trying to induce bets from underpairs. I take that the colours on your Flop did not hit the suit of your hole cards?

At 2nl don't bluff the fishes. By that I mean, don't go into fancy play syndrome, which you did in this hand. All this sophisticated reasoning to play that bluff leads to you leveling yourself away from your money. The fact of the matter is, your opponent is liking his hand and will never fold. So AP, fold that Turn.

Be VERY selective of which spots to bluff. Small hint, at 2nl, plenty of villains checks when a scare card hits. That is a good place to attempt a bluff at a cheap price.

I wouldn't assume a narrow range UTG, I'd assume it to be more narrow than a later position however. We can squeeze here profitably imo, as a bluff yes, but also ahead of some suited broadways, an overcard to JJ etc and lots of good flops. Calling behind is fine as well, but if we want to bluff at all this is one of the combos that plays best.

Because of the assumption about his range preflop, we now assume an overpair at best or more often 2 over cards. This makes us think that we can float with any 2 cards. Which is false, because we have no real idea about what range he is taking to the flop.

Raising the turn with only showdown value and no outs to improve is spewy vs a range that can have straights, sets, overpairs, nut flush draws. Folding out only airballs some of which we beat.

Fold flop imo, at least have a back door draw or gutshot before floating

You should always tell suits of your hand. If you dont have FD the main mistake is flop call.

All three options are fine preflop if you can play it well postflop; which you didn't. I'd lean for a squeeze pre though as this is the perfect hand in the perfect position to do it if the two players before you are reggy.