If you find there's plenty of water in the fresh tank and this continues, go look at your city water inlet while the pump is running. On my trailer (MUCH older than yours) the check valve doesn't work, so if I don't have the fresh water inlet securely capped the pump will never build up pressure, and water comes out the city water inlet.
Il Carriaggio — 1975 Argosy 24 | Il Progetto — 1976 Argosy 28 Center Bath | WBCCI# 15566
He has all of the virtues I dislike and none of the vices I admire. — Sir Winston Churchill