No power to house batteries?

I am assuming the main circuit breaker in the RV and the circuit breaker for the converter/charger are turned on.

Start at the house. Check to see if the outlet the RV is plugged into has power.

If that outlet has power, next check to see if the main breaker in the RV has power both into it and out of it.

If power is coming out of the main RV breaker, check to see if power is coming out of the breaker to the converter/charger.

If power is coming out of the breaker to the converter/charger, check to see if DC power is coming out of the converter/charger.

Report back for further narrowing down of the possiblities.

Is your battery disconnect switch in the correct position? If you can pull the red handle out, the battery is disconnected. Turn it to the other position.

Sorry l forgot mention that I do have 120 and 12 volts at the breaker panel. I have no disconnect switch in line.

You should have a disconnect somewhere May say USE/STORE or AUX on/off

Also you should have a circuit breaker or fuse in line. Likely close to the battery but mine was about 15 feet down the power road.

also there are fuses on teh converter.

Question... Do the lights get brighter when you plug in? (Converter is working)

Next question You said 10 volts. 1.414 times 10 is 14.14 I point this out because if the meter is set wrong you may be showing 70.7% of the voltage (The inverse of the square root of 2 times the voltage) has to do with the meaning of RMS on some meters. (Some meters if set to AC read the peak and multiply by .707, others read the true RMS and are not so affected).
I have both kinds.