I have a 6 month old puppy who was house trained before we got her now she pees inside, even after tireless efforts of taking her outside a lot

Well, I have a cat that does that she knows where her litter box is and she uses it all the time but if she walks around the house and smells wet towles or clothes she will go potty on them so maybe your dog smells something? Try getting wee wee pads? Better then going on the carpet, if they pee put there face near it say NO and put them outside for awhile But you should write down what you do when she pees on the floor

try getting wee wee pads? better then going on the carpet, if they pee put there face near it say NO and put them outside for awhile But you should write down what you do when she pees on the floor

Pads are very good for training your dog to urinate INSIDE.

Sticking their face in it and disciplining them is called aversion training. You won't find many advocates for it on this website. It's anxiety inducing and only moderately successful.

At a guess, she has some anxiety about a new home already.

Continue taking the pup outside and don't go back in until she goes outside (sorry for the pun, I couldn't resist.) Praise her for going then go inside and snuggle or play a little.

Also, have her kidneys checked on her next vet trip.