From what I've read so far, this is an EXTERNAL Giveaway promotion.
The thread starter is promoting a community/forum called myStellar.org
there, they have numerous activities and promotion to earn Stellar Lumens,
In order to participate, you'll have to be a registered member, join discussions and create topics/threads in the said forum.
None of you should post/reply your wallets here, the giveaway is NOT happening here on bitcoingarden but on myStellar.org.
(I made this reply to clarify things since many newbies are complaining, I hope it helps.)