Sounds like you have your answer but I agree with the others who say, why is he crated while you are home? It is more work for you to watch him but people trained puppies for years before crates became popular.
Personally I am not a fan of crates. I will never again follow the adage that says to make it so small puppy can do no more than stand up, turn around and lie down. In the odd event pup has an accident or you are detained pup is stuck in her own pee, poop or puke. If a crate is needed then it's going to be as big as possible for me.
My Vet supposes that too long crate time in too small a crate might be responsible for the increase he sees in UTI, behavioural issues from being bored and joint issues from not enough movement whilst growing. I don't know of any research to confirm this but it seems reasonable.
We did use a crate but the door was open and it was in a pen for our first pup and our gated kitchen for the second. The odd time they had to bathroom they chose a spot as far from the crate as they could. Mostly we got them out in time to learn outside was the preferred place.
Some tips on potty training. Puppies do not develop complete control till they are about 6 months old. They will try to hold on, something every woman's Doctor has advised her not to do, that's what leads to UTI and loss of control in later life, same for dogs.
A little trick that might help is to place food and water dishes right on top of accident spots. After cleaning them with a biologic that removes the scent of pee or poop of course. They don't want to eat near their toilet. If you establish your whole kitchen floor as a possible eating spot pup will ususally not want to toilet there.
Please be very, very cautious of leaving bedding and toys in the crate when you are not there to supervise. Bored puppies chew and swallow, bingo, obstruction. They are fine with no bedding.
Can we see your puppy? Photo?
