BT shield pairing code


I’m using a seeeduino bluetooth shield ( with my arduino uno REV 3 to connect with a master bluetooth device wich has a predeterminated (“12345678”) pairing code. But after trying to connect and to input the pairing code from my arduino I realised that this shield use only 4 digit ( “1234” ) pairing code ??? Is this true or I’m wrong ? ( I tryed to connect from my cell phone and if I set a “12345678” as pairing code it does not connect, with a “1234” pairing code it does )
Is there anyway to change or update the shield’s firmware?

Thank you!

maybe you can delete the old pairing and repair it again. we always use “0000” as the pairing code.