Kind of a general question to answer without knowing other parts of their post flop strategy or without knowing your cbet frequencies.  If they are folding a very low frequency you should stop bluffing low fold equity flops altogether. Also what does their probe frequency look like, some guys are only probing a low frequency with value, vs them you check back flop and have a more profitable delay cbet vs a weaker range. You should be trying to take more hands to showdown vs them and less of cbetting hands like ace and king to fold out equity share when you usually aren't folding out better or getting called by worse.  Try putting your bluffing range into different lines, if your standard is just to put all your air into a cbet give up on the turn strategy and fold to a river bet unimproved these kind of players are going to really exploit that. Vs that strategy feel ok about not putting another chip into the pot postflop on boards your getting called or checkraised a higher frequency on and try and realise your equity just checking back more.  You also said some of them are barreling you like crazy and its hard to get to showdown, vs them you are gona have to checkraise less value hands on the flop to protect your calldown range. If your standard is to always checkraise strong value that leaves your checkcall range ( of 2nd and 3pairs )  hard to call down unimproved on later streets which can be exploited by a aggressive barreling strategy.