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Test result for nxtcld01.ad.kellerautomation.com using http-01

No valid A or AAAA records could be ultimately resolved for nxtcld01.ad.kellerautomation.com. This means that Let's Encrypt would not be able to to connect to your domain to perform HTTP validation, since it would not know where to connect to.
No A or AAAA records found.

Submitted Dec 28 14:55:35 2021. Sat in queue for 2ms. Completed in 0s. Show verbose information.