Depending on your problem there are different HN and mailing lists to post to:
general NAF problems: naf-helpdesk@desy.de
NAF ATLAS support: naf-atlas-support@desy.de
ATLAS specific problems: https://groups.cern.ch/group/hn-atlas-gridka-cloud-user-support/default.aspx
ATLAS D Computing Resource Board: https://twiki.cern.ch/twiki/bin/viewauth/Atlas/AtlasDComputingResourceBoard
Write to NAF ATLAS support if you need a ATLAS NAF account, more AFS quota, an additional AFS volume, request additonal ATLAS releases, etc. For everything else start with the GridKaUser HN. xxx