A C-level sponsor is the strongest lever a program has. Most TPMs waste it, either by hiding problems to look competent or by escalating everything and becoming noise. Both burn the relationship.
The thing a sponsor wants is no surprises. They can absorb almost any bad news if they hear it from you early and with a plan attached. What they can't forgive is finding out about a slip from someone else, or learning a risk became a crisis while you sat on it. Early and honest beats late and polished every time.
I bring a sponsor two things and nothing else: the decisions only they can make, and the risks only they can clear. I don't bring status, they can read status. I don't bring problems I can solve myself, that just trains them to think I can't. I bring the things that genuinely need their altitude.
The other half is doing the homework before the ask. A good sponsor will move fast if you hand them a clear decision with the options and a recommendation. Hand them a vague problem and you've made your problem their problem, which is exactly how you lose their time and their trust.