Already participating in championship


the official Microsoft Forum brought me here and I hope you can help me. So I’ve been playing Forza for the last two months or so and I never had any problems, but this summer I can’t participate in any racing challenges. I can do the weekly Forzathon challenge and also the PR-stunts. When I try to start any racing season event it always gives me a warning before the race that I’m already participating in another championship and if I want would like to cancel the current one. If I press no I can’t do anything and if I press yes I start the race, but apparently not the summer games challenge.

Anyone with similiar problems can help me out?