I have a warning display on DP saying ( Battery 1 low 13.4 volt) nothing seems to be working properly. What should i do?

I’m receiving a warning display on DP ( Battery 1 low voltage: 13.4)
nothing seems to be working properly. Desperate for some help

If you have a meter and you are hooked to shore power. Disconnect the shore power and test the battery to see what it is actually reading... . 13.4 volts is a good reading. You may have have to reset your display panel