Message_type_x in CNDP

Hi Experts,

When i am converting the internal table content in to PDF using the function module 'CONVERT_PAYSLIP_TO_PDF'. When i am debugging in the function module the its not throwing the dump error, When the data is downloaded using the function module 'GUI_DOWNLOAD' at the end i used the message class, At that time its throwing the dump error as

"MESSAGE_TYPE_X" for message class"CNDP"

please can one help with this

Regards,

Mohan