The error might be an incompatibility issue since you said the EEPROM you flashed came from another unit am I right?

It won't work you need an EEPROM that came from another dashboard but on the same unit.

The hashboard must be synced if the serial numbers are different the control board won't recognize it.

There is a way to bypass this if you don't have Eeprom backup on that unit.
To bypass this you need to boot this unit with Braiins OS.