Hi Ram Kumar,
I suspect, the configuration of personas is not completed successfully. The FQDN might not set properly.
Please go through the below links and re-configure it again and check.
SAP Screen Personas - How to configure the system (troubleshooting FAQ)
SAP Screen Personas Configuration Guide Addendum
Configuration Check - SAP Screen Personas - SAP Library
Hope this helps you.
Regards,
Rama