Using following log searches should provide a failure reason:
2025-06-30T20:45:39+02:00 2025-06-30T18:45:39Z ERR Error renewing certificate from LE: {wiki.domain.tld []} error="error: one or more domains had a problem:\n[wiki.domain.tld] invalid authorization: acme: error: 403 :: urn:ietf:params:acme:error:unauthorized :: 1.2.3.4: Invalid response from http://wiki.domain.tld/.well-known/acme-challenge/63nMJK_Q5oeZci_U1cq-cRx6JZNKsdfafasdfasdf: 404\n" acmeCA=https://acme-v02.api.letsencrypt.org/directory providerName=acmeServer.acme
We could also check if the right port is opened and if DNS is setup correctly.