Bathtub doesn't drain into sewer

I just bought a mobile home and learned that the recently updated bathtub does drains under the trailer instead of into the sewer line. There is also no water coming out of the bathroom sink, but the toilet works fine. What could be the issue and how would I go about fixing it?

I have already checked to make sure the water is turned on for the sink and have been told that I may need to reroute the pipes to attach to the sewer line.

Bathtub doesn't drain into sewer