We are providing certificates installation automation for our clients. Using acme v2 protocol.
The load to let's encrypt endpoint is pretty low, just a few requests today (Nov 25, 2021) but when creating order and then getting authorization order details we receive error "Rate limit for '/acme' reached" .
We've checked this doc Rate Limits - Let's Encrypt and found no rules that we might violate.
Need your assistance. We can provide more details about the order if you need.
Can this be connected with your 'Service status: Degraded Performance' ?
It could very much be related to the services degraded performance. I'd advise you to note the outage to customers who enquire then wait for the issue to resolve.
Let's Encrypt does not provide a service level agreement. For business continuity planning you may wish to investigate other ACME CAs (ZeroSSL, BuyPass GO etc) and build in the ability to easily/automatically switch CA (or try one, then another).