401 - Unauthorized: Access is denied due to invalid credentials. You do not have permission to view this directory or page using the credentials that you supplied.

Issue:-
Unauthorized: Access is denied due to invalid credentials. You do not have permission to view this directory or page using the credentials that you supplied. while requesting a Service in vRealize Automation.

Reason:-
It was because of vCenter Inventory Service.

Solution:-
Restart vCenter Inventory Service.