well, if it's part of the faucet assembly leaking, you may need a new faucet assembly. Look at the fittings where it connects to the water lines. When in the hardware store, get a new faucet that will fit the same holes and connect to the same fittings.
If under warranty, call heartland customer service at
877-262-8032 /
574-262-8030. Have your vin # ready. They will probably be willing to send you a faucet for self install.
If you don't want to install a new faucet yourself, you'll either have to take the trailer to your dealer, or find a mobile servicer and pay the travel charge.