Treat them like a paused customer that may come back.
A great SaaS CEO recently said to me, “For every customer we lost in the early days, we actually lost them 3 more times. Because our contact went on to another company — and didn’t buy us there. Or the next time.”
Treat a lost customer as a customer just taking a pause. Maybe even as still a customer. Just an inactive one.
It’s a journey. Maybe they come back in a year or two. Maybe they never come back, but go to another company, and deploy you there.