Music is playing alone and switch automatically

[Jackcroft]

Plan : Premium / Country : FR / Device : Iphone 7 / Operating System : iOS 11.4.1

 Hello guys, 

When I start my spotify app, I always have a message about a web player using my account and I can see some music from artists I don't know have being played when I didn't used my app.

So I changed my password, uninstall and reinstall the app, and I still have the same issue.

The most unconfortable issue is sometimes my app play music 10-20 seconds and switch automatically to the next song or to an artist I don't know.

Please, ho can I fix it ? 

Many thanks