A couple of problems. First off, what is your battery capacity, and how many watts of solar are you charging with? You say you were running the system for about 6 hours before this point? What was the load you were running, and how many watts was that?
All indications are that you drained the battery dry and you are not recharging it.
Did you first connect the controller to the battery before connecting the solar panels? The controller needs to boot up first ONLY on battery power before the circuitry can properly accept the solar input.
Lastly, you appear to have your battery wired improperly. The two input wires from the controller and the two output wires to the inverter are both connected to the same battery. That is incorrect, and will result in the premature death of the top battery.
For correct wiring, the black and red paralleling wires should stay the same. However, both blue positive wires should be relocated to the positive terminal of battery #1 (top one), while the brown negative wires should stay on the negative terminal of battery #2 (bottom one).
If the static voltage is now to low to properly boot up the system, you might have to break it down and charge each battery individually with a battery charger to full charge, then start over.
