hmmmmm
What voltage is the controllers showing, The battery or the panels?
What controllers do you use?
Have you recently worked on the rig so that you needed to cut the power from the panels to the controllers? Maybe disconnected a fuse or switch, possibly pulled the wire from the panels to the controller inside or at the panels?
Starting with the lines coming from the panels, disconnect them and test for voltage there. If you are getting what you expect to then reconnect them and test for panel voltage at the controller. You may not even have to disconnect them from the controller to test them. just touch the screws that tighten the wires into the controllers.
If you have good voltage up top and at the controller/s then check your settings. Possibly the controller needs to be reset by first disconnecting the panels and then the connection to the batteries before reversing the process.
Could you have disconnected the batteries but not the panels? Some controllers this is a big no no. I know that my Morningstar controllers do not like to have the battery disconnected while the panel is still producing power and they can die from it. Other controllers do not seem to care.
I have seen where a Victron controller became disconnected from the bank when the wire melted. Everyday the controller came on, appeared to go thru bulk, absorption and float showing normal voltages and shut off as soon as the sun went down or the panels were disconnected. The panels were powering the controller while the batteries were down into the 11's because they were not receiving any power. We replaced the wire going to the batteries and all was well again. So make sure that you are seeing the proper voltage at the bank, on both ends of the fuse and at the terminals of the controller
The last thing that I can think of is has the controller been disconnected and if so, did you re set it up. Some controllers will not start working unless you tell it the voltage of the bank first.
Hope it helps
