To prevent this situation from happening, it's recommended you add a standard email and password login and associate that to your account by following: https://meta.stackexchange.com/questions/793/how-do-i-change-my-login-providers.

If you are already unable to use your current login provider, you can use the form to create a new account and use the same email address while registering. Once you've verified your email address on your new account, in most cases, the new account will be automatically merged into your existing account and will have the new login method imported. In some cases (such as if you're a moderator on any site, or if the system couldn't verify something), the automatic merge will not happen; if that happens, [request that your accounts be merged](https://meta.stackexchange.com/questions/18232/how-can-one-link-merge-combine-associate-two-accounts-users-anonymous).