This field shall provide the setup PIN code as a text string at least 8 characters in length or empty string to indicate that the accounts do not match.
NOTE
Newer cluster clients should be aware that AccountLogin cluster version 1 specified an 11 digit minimum length.
This message is sent in response to the GetSetupPIN command, and contains the Setup PIN code, or null when the account identified in the request does not match the active account of the running Content App.
See
MatterSpecification.v13.Cluster § 6.2.4.2