Amazon Alexa (Echo) and Iphone on Family Account

[jof0366]

I have a family account with a specific username and have linked that username with my Echo as the default music service. The user name is linked to my email address. I also have spotify on my iphone and have logged in using my email address.

However, when the echo is playing music  I can't play music on my iphone. I was travelling today and the echo was on playing at home and everytime i tried to play music on my iphone it popped up with a choice - echo or iphone but I want both and to listen to different playlists on each

Please help me solve this