HU cash game effective 300BB. No rake.

Hero BB position with 6h 6d.
Villain raises from button 70% of the time. 3BB
Hero 3-bet to 10BB
Villain 4-bet to 25BB

What should I do here? Villain does 4-bet preflop about 1% of the time. There was once he flat called my 3-bet with AKo at button.

What do you do here with sixes? What does a solver suggest I do here?

Anyway, I called. I felt that since he would hide the strength of his card like AK, he probably is 4-betting with not-so-strong hands from button like Ax

Flop was Js 5h 8h

Hero checks.
Villain bets 22BB.

What should I do here? What would a solver suggest I do here?

what's the sample on any of these. what's his overall 4b. what would you profile him as in terms of general playstyle

Not enough info

If he 4bets around 1%, then his 4bet range is probably around QQ+

I haven't ran the hand through a solver, but I like the preflop call of the 4-bet most of the time when you're that deep. I actually like calling more against tight players who will stack off when you hit a set.

I would likely call the flop bet as well against most players.

Your 3-bet frequency is relevant because I would expect him to 4-bet wider if you're an aggressive 3-better. So if you 3-bet a lot preflop that weighs in favor of continuing against the flop bet, assuming he is aware enough to be adjusting. If he still 4-bets super tight pre even though you 3-bet wide then I would just fold to the flop bet.

However if his 4-bet percentage is reasonably wide I'm thinking you have to continue on the flop. You can win at showdown sometimes when he gives up on his bluffs, and there are turns that give you additional equity to continue if he keeps barreling.

Now I will give the disclaimer that I may be wrong, but I want to test myself before someone else runs it through a solver.

solver would say call then call

in practice likely just calling pre (not 3betting) is good despite his super low 4bet %