Let's Debug

Test result for solv.sec.samsung.net using http-01

A private, inaccessible, IANA/IETF-reserved IP address was found for solv.sec.samsung.net. Let's Encrypt will always fail HTTP validation for any domain that is pointing to an address that is not routable on the internet. You should either remove this address and replace it with a public one or use the DNS validation method instead.
10.199.2.15

Submitted Oct 19 01:47:29 2021. Sat in queue for 10ms. Completed in 3s. Show verbose information.