Fiori and Main Menu not working

Hi All,

I'm experiencing some intermittently issues on SAP B1 HANA clients. One day the fiori dashboards show and then the next day it doesn't and comes with an error FATAL ERROR:XS_HOST_NOT_FOUND.

The XS Engine at both ports 4300 and 8000 are started and user and access it.

Users aren't all superusers but happens to superusers as well.

Please assist as I'm running out of patience.

Regards

Lou