When Public aid is secondary you need to send the Primary TPL code with the claim.
TPL codes can be found here
The error message is for 3 Digit TPL code and 2 digit TPL status code for secondary public aid claims.
Step 1) The Primary Insurance should have the 3 digit TPL code and "Requires TPL for Secondary should be checked in Insurance Master.
Step 2) The Claim should contain the 2 digit TPL status code (reason why primary paid or did not pay). Edit the claim from Manage claims and set this
Refile the claim once both the above steps are completed.