Can't create a giveaway for my group!? (whitelist)

Maybe you should sync with steam

This has happened with other groups. It takes a few days for the group to be added to the system I believe.

Firstly it takes time for groups to show up on steamgifts, as others have said. Steamgroups are not synced the same way users are, periodiclt steamgifts updates all groups.

Secondly steamgifts sometimes has troubles with non alphanumeric characters in group names. it is possible that the hash in your groups name is causing an error. To be fair the only other example of this I've seen involved the ♥ character which is more non standard then the hash.