Manually reset your team.
To do this you have to:
1. Click your profile at the top left
2. Click on settings
3. Click on Team
4. Scroll to the bottom
5. Enter the sentence: "I do wish to reset team"
If you've already started playing again, and feel this is a setback - im afraid this is the only way to get into a league without creating a new account.
Happy ELO grinding!