Letsencrypt Auto renewal fails - Error getting validation data

Troubleshooting
13 
root@DietPi:~# cat /etc/lighttpd/conf-available/10-proxy.conf
# /usr/share/doc/lighttpd/proxy.txt

server.modules   += ( "mod_proxy" )

## Balance algorithm, possible values are: "hash", "round-robin" or "fair" (default)
# proxy.balance     = "hash"


## Redirect all queries to files ending with ".php" to 192.168.0.101:80
#proxy.server     = ( ".php" =>
#                     (
#                       ( "host" => "192.168.0.101",
#                         "port" => 80
#                       )
#                     )
#                    )

## Redirect all connections on www.example.com to 10.0.0.1{0,1,2,3}
#$HTTP["host"] == "www.example.com" {
#  proxy.balance = "hash"
#  proxy.server  = ( "" => ( ( "host" => "10.0.0.10" ),
#                            ( "host" => "10.0.0.11" ),
#                            ( "host" => "10.0.0.12" ),
#                            ( "host" => "10.0.0.13" ) )
$HTTP["host"] == "mydomain.org" {
    $HTTP["url"] =~ "^/notifications/hub($|/)" {
       # WebSocket proxy
      proxy.server = ( "" => ("vaultwarden" => ( "host" => "internalIP", "port" => 3012 )))
      proxy.forwarded = ("for" => 1 )
      proxy.header = (
           "https-remap" => "enable",
           "upgrade" => "enable",
           "connect" => "enable"
      )
   }
   #} else {
   $HTTP["url"] =~ "^/vault($|/)" {
      proxy.server = ( "" => ("vaultwarden" => ( "host" => "internalIP", "port" => 8001 )))
      proxy.forwarded = ("for" => 1 )
      proxy.header = ( "https-remap" => "enable" )
   }
   # }else {
   $HTTP["url"] =~ "^/paperless($|/)" {
      proxy.server = ( "" => ("paperless" => ( "host" => "internalIP", "port" => 8000 )))
      proxy.forwarded = ("for" => 1 )
      proxy.header = ( "https-remap" => "enable" )
   }
   #}
}