Violation of PRIMARY KEY constraint 'FXXXX_PK'. Cannot insert duplicate key in object 'XXXXX'.

Hello experts,

    We have a PROXY-JDBC (3rd party's SQL database ) scenario in SAP PI 7.31. When proxy is got triggered from SAP. For some messages getting the error :

    Violation of PRIMARY KEY constraint 'FXXXX_PK'. Cannot insert duplicate key in object 'XXXXX'.

    The primary key maintained in table is MESSAGE GUID. In PI this field is mapped to currentDate (ddMMyyyyHHmmssSSS).

    This error is getting only for some messages. Rest of all are processing successfully. This issue is happening in production and its a bit urgent.

    Experts, kindly give your inputs on this. Thanks a lot in advance.

Thanks

Ravi Kiran.