How can I verify if our SSL certificate is active?

I help a friend who has a hobby store with his simple, one-page website. I really don't know much about web hosting. A week ago the hosting company sent an email saying the SSL cert was going to expire. I asked via email what I needed to do and they said it will be fixed. Today I got an email from them asking if I was satisfied with their handling of my question. Nothing that said they did anything.

How can I verify it is fixed?