Client question

What do you do (or have you done) to apologize to a client for a lapse in service?
And when you first began your business, what were some of the reasons why you lost touch with a good client? It’s not OK to do that with friends, even though it happens, but never with businesses.

I have no excuse for my mistake. I designed a portfolio-quality website for a church before I moved to another city. I had to settle in, find an actual job, get liscense and ID changed, the usual settling in stuff. But updating their website fell through the cracks. My stuff is still on their server and it’s remained unchanged.

Thanks for your advice. Hopefully I won’t do this again.