Have a oki printer c531 its now showing service call 231 any help

https://www.youtube.com/watch?v=5C2KAer0818

You have a possible problem with the secondary card; harware problem. Cost of fixing it vs. buy another printer.

231 means RFID reader I/F error. 03 means Communication error
between the RFID reader and the tag chip. The remedial measure is to check for normal connection of the antenna cable.

Error 231 could be caused by multiple issues. The RFID R/W PCB, CU/PU PCB just to name a couple. This might be best left to an authorized service agent.

Replace the RFID R/W board.

I tried putting 1.5mm of plastic foam under the RFID chip to raise it up in the toner cartridge. This seemed to work.

Please list the error message exactly as it appears in your window

Write down the message including the error number "nnn,".

THE RFID READER IS NOT CONNECTED CHECK CONNECTER TO THE LED'S AND TO THE BOARD AT THE BACK OF THE MACHINE

From the service manual, doesn't look good.
A technicain will have to look at the printer.

RFID Reader I/F Error
An interface error was detected with the RFID reader device.
01 : communication error between the RFID reader and the engine PCB.
02 : the transceiver circuit error of the RFID reader.
03 : communication error between the RFID reader and the Tag chip.
04 : the RFID Tag detection error (more than 4 chips).
If rebooting the machine does not improve the symptom, you need to
check the device.