Spotify login error

I have a premium account in spotify and use it in my iPad.
I also use djay 2 in the same iPad.
Two programs worked perfect together.
BUT after I put spotify (using the same premium account) and djay2 in a second iPad, djay in both iPads fail to login spotify and gives the message:
Spotify login error.
User needs a premium account (15)
What I’m I doing wrong? Please help

Finally solved it. I did login using my Facebook account

Finally solved it. I did login using my Facebook account (in fact that’s the way I login to spotify my first time)

i have the same problem