Let's Debug

Test result for bbb.mahale-ggmbh.de using http-01

A private, inaccessible, IANA/IETF-reserved IP address was found for bbb.mahale-ggmbh.de. 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.
fe80::4cd3:54ff:fee3:105c

Submitted Feb 17 15:34:41 2023. Sat in queue for 4ms. Completed in 2s. Show verbose information.