TCS have been linked to the Marks and Spencer breach, at least in part.
I made this point a few weeks ago, but... outsourcing all your IT, Networks, Service Desk (helpdesk) and operational cybersecurity is a temporary cost saving and basically paints a ticking timebomb on the org, IMHO.
@GossiTheDog I must admit to not being particularly enamoured by the overall concept of third party identity security services.