Error while updating secure LDAPS in Azure AD DS

I'm attempting to turn on Secure LDAP and have followed the guide at https://video2.skills-academy.com/en-gb/azure/active-directory-domain-services/tutorial-configure-ldaps - unfortunately I am experiencing error messages - both that the domain is busy and a "RequestConflict" error that gives the message "Cannot modify resource with id '/subscriptions/<<ID>>/resourceGroups/DMA-AD/providers/Microsoft.AAD/domainServices/<<domain.com'>> because the resource entity provisioning state is not terminal. Please wait for the provisioning state to become terminal and then retry the request."

I do see domain services are running from overview page.