This is happening to one user as of now. When trying to submit a request the following issue appears:
Error occurred while submitting this request. Please contact the administrator.
Release : 17.3
Component : Catalog - Request Creation
The account does not exist and can't be created.
Create the account for the user.
Go to the Administration tab > Business Units > Click on the BU > Click on the "Add Account" button (right corner) and in the account settings, search and add the user with the problem, then click OK to save changes.