How to I delete my synced data from firefox sync

Hi! I think I accidentally signed in to firefox sync with this account so it synced all my passwords and stuff. But I cant login any longer because I it wants to send confimation code to my email. Signin in to this forum works fine for some reason but not to accounts.firefox.com anymore. The problem is that I used 10 minute e-mail service to create this account so there is no way to access that confirmation code. So anyways I want to have my synced data deteted because I don't trust Mozilla with my private data. What are my options?