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Did you delete the private keys for all of the certificates you requested?
Renewals are treated specially: they don’t count against your Certificates per Registered Domain limit, but they are subject to a Duplicate Certificate limit of 5 per week. Note: renewals used to count against your Certificate per Registered Domain limit until March 2019, but they don’t anymore. Exceeding the Duplicate Certificate limit is reported with the error message
too many certificates already issued for exact set of domains.A certificate is considered a renewal (or a duplicate) of an earlier certificate if it contains the exact same set of hostnames, ignoring capitalization and ordering of hostnames. For instance, if you requested a certificate for the names [
www.example.com,example.com], you could request four more certificates for [www.example.com,example.com] during the week. If you changed the set of hostnames by adding [blog.example.com], you would be able to request additional certificates.Renewal handling ignores the public key and extensions requested. A certificate issuance can be considered a renewal even if you are using a new key.