FORTINAC Certificate Management Error

I would like to seek your help and inputs on FortiNAC, as we have a VM based running on version 8.3. We are trying to generate CSR to generate a new Cert from the Internal Root CA. However, we are getting this Certificate Management error as attached below. Also, when trying to generate CSR, the certificate target is not displaying any options (Admin UI, PA, Portal). Hence, only display an empty dropdown menu.

Does anyone experience the same or have any thoughts on workarounds? 

Thank you and appreciate all your inputs.