Multiplus II 12/2000/120V trips when connected to shore power

Multiplus II 12/2000/120V connected to house battery bank trips every time I connect to shore power.
It should automatically switch to shorepower from inverter when it detects the grid, but it hasn’t been doing that. I’ve tried switching the toggle from invert to charge only at the box (manually) and neither position solves the problem.

Everytime I turn on the charger breaker on my panel, it trips the entire dock. I’m not popular with the neighbors!