I have a Tycon MPPT solar charge controller. My batteries are wired for 24V, but they are so low the controller thinks they are 12V batteries and won’t charge them

The MPPT charge controllers by default are set for 12V/24V auto detect. Using the keys on the front of the unit go into the settings and set for 24V battery instead of 12/24 auto detect. Save the setting. Power down the unit by disconnecting the solar and then battery. Power up the unit. It should power up in 24V battery mode. Re-connect the solar input.