Late reply apology
When to use: Use this when you are replying later than the customer deserved and want to own the delay.
Subject
Sorry for the wait -- here is the answer on topic
Hi customer name,
First, I am sorry it took us longer than it should have to get back to you. You reached out about topic and deserved a faster reply. That one is on us.
Here is where things stand: answer. If any part of that is unclear or does not solve it, tell me and I will stay on it until it is sorted.
I would rather you never had to wait, so I am flagging this thread to make sure your next reply comes quickly. Thanks for your patience with us today.
Best,
your name, company name