Analytics account is not connected to DTM Account. A DTM admin would have to add you as a user in their DTM account and then you will receive your credentials.
I'd recommend contacting a DTM Admin in your company to get access.
Who is the DTM admin? I have full access to Adobe Analytics. Can someone please make me the admin? Our Account Manager from Adobe is email@example.com. Can you please tell him how to make me the admin?