Hi Shawon786
I am using latest version of ERP and latest version of wordpress (erp 1.1.11 and WP 4.7.2)
The strange thing is I had this error in the schedule page, the main overview page of crm module.
This was gone when i updated erp to version 1.1.10. This solved the same problem on the schedules page, but the problem moved to the template page.
So now schedules are working fine, no errors, but templates is not working anymore.
I cleared the cache and tried with different browsers, no luck.
I am also running w3total cache plugin, could this be of influence?
Thank you.