Getting the upper hand back

[Erin O'Connor Smith]

My lease with my new tenants states they need to provide proof of renters insurance within 30 days of moving in. I sent a gentle reminder that this was past due. I received a reply stating that it was buried in the lease and that he needed more time, and if it had been so important why haven’t I mentioned it in our several other conversations? Let’s just say it had a snarky tone. I have not responded but want to now that a few days have passed and I had a chance to pause. What do I say to regain control of this situation? I am on site virtually every day this month overseeing the renovation of the house next-door and would like to maintain a firm but cordial relationship.