Let's Debug

Test result for cert.dopark.xyz using http-01

A private, inaccessible, IANA/IETF-reserved IP address was found for cert.dopark.xyz. 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.
A and AAAA records found for this domain
cert.dopark.xyz. 0 IN A
The IANA public suffix is the TLD of the Registered Domain
The TLD for cert.dopark.xyz is: xyz
The current status.io status for Let's Encrypt

Submitted Oct 18 05:22:37 2021. Sat in queue for 8ms. Completed in 1s. Hide verbose information.