I have a teacup chi that I bred and a jack/ chi mix and they can go all day in their crate when I am not home... but even on days when I am home they only need to go out about three times a day... the only time mine have ever had accidents in the house is when guests bring their dogs into the house and they "mark their territory"
If you have only had the dog a little bit it could be having to relearn things. Nerves and big changes in a dogs life can wreak havoc on them. Maybe try when you are home timing it so they learn to go outside again. Depending on how long you have had it you could just need to refresh adn train them at your home.
Puppy pads worked great for my guys when they were still babies and they couldn't hold it all day
I use puppy pads with my Chihuahuas and they do well with those. With a crate, you need to make sure it is big enough for the dog to turn around in and that's about it. Dogs won't sleep in their waste. If they have too much room, the dog will sleep in one section of the crate and go to the bathroom in another.
I'm sure a lot of the behavior has to do with a new environment, etc.