Hello,
Seems certs do not actually auto renew as promised!
"Will be automatically renewed ..."
"Each of the certificates below helps to avoid a security warning in a browser, will be issued for 12 months, and has a warranty."
I just needed to manually renew dozens of domains on my server which was set up about 3 months ago. Why would let's Encrypt claim they would all auto renew if this isn't true?
Also, given that Let's Encrypt doesn't run any clients, LE doesn' claim that anything auto-renews. LE recommends subscribers/client implementations to have auto renew features, but this is really not in their hands.
The vast majority of clients out there try auto renewing wherever possible.
There's also no warranty of any kind, so wherever you got that statement from - it's not from ISRG or Let's Encrypt.
You can look at your current certs and see which CA they were provided by. Most likely they were purchased from a hosting provider and they warrant them as well as renew them for you. If they haven't renewed the certs, whoever you purchased the certs from are the ones to be questioning.
Is this server the same? If so, and you are using win-acme, check your windows scheduled task for win-acme is running regularly. If not win-acme then please specify exactly what you are using.