Hi Veysi,
ı had the same issue and after lots of support tickets none of Microsoft support workers could solve my problem. Microsoft really doesn't know what they sell to customers. I solved my own problem. Problem is that Microsoft doesn't offer Outlook for Mac for Turkey region. Go to active users and click edit user. On left side click on Licences. You will see users region there. Temporarily change your region to USA or UK then go to Software page and you will see download link. After download you can set your region back. ı hope this helps.