Settings > eholdings > Assigned Users > Attempting to add a user to a second set of credentials results in a length loading indicator

Using snapshot

1. Go to settings > eholdings > Assigned Users
2. Assign a user to one set of credentials
3. Then try to add a user to a second set of credentials
4. Error displays as expected
5. BUT the page does not return to the Assigned Users page
6. Instead is displays lengthy loading on the detail record