I entered the wrong age when setting up Sync and now it won't allow me to create an account.
Setting up a Sync account I entered my age as 1 instead of 41. I now cannot create an account because Firefox is remembering my age as 1 and I get an error message saying I am not old enough to create a Sync account,
Wšě wotmołwy (2)
Hi
If you type about:preferences#sync into the address bar and select "Manage Account", you will have the option to delete your account.
You can then set up a new account and apply those details to your second device so that Firefox Sync will be able to connect to it.
Try clearing your cookies and then try to set up a new account again.