Getting "Unable to retrieve configuration parameters from the extension : value does not fall within the expected range"

Hi,

In our environment we have installed the custom connector for "Generic REST API Management Agent (eiIdentity)". While creating that MA in FIm sync by selecting "Generic REST API Management Agent (eiIdentity)" from the "Management Agen for", we are getting an error "Unable to retrieve configuration parameters from the extension : value does not fall within the expected range".

Colud you please help me out how to resolve this error.

Thanks

Prasanthi.