Thrown if there already exists an account with the email address asserted by the credential. Resolve this by calling firebase.auth.Auth.fetchSignInMethodsForEmail with the error.email and then asking the user to sign in using one of the returned providers. Once the user is signed in, the original credential retrieved from the error.credential can be linked to the user with firebase.User.linkWithCredential to prevent the user from signing in again to the original provider via popup or redirect. If you are using redirects for sign in, save the credential in session storage and then retrieve on redirect and repopulate the credential using for example firebase.auth.GoogleAuthProvider.credential depending on the credential provider id and complete the link.
auth/credential-already-in-use
Thrown if the account corresponding to the credential already exists among your users, or is already linked to a Firebase User. For example, this error could be thrown if you are upgrading an anonymous user to a Google user by linking a Google credential to it and the Google credential used is already associated with an existing Firebase Google user. The fields error.email, error.phoneNumber, and error.credential (firebase.auth.AuthCredential) may be provided, depending on the type of credential. You can recover from this error by signing in with error.credential directly via firebase.auth.Auth.signInWithCredential.
auth/email-already-in-use
Thrown if the email corresponding to the credential already exists among your users. When thrown while linking a credential to an existing user, an error.email and error.credential (firebase.auth.AuthCredential) fields are also provided. You have to link the credential to the existing user with that email if you wish to continue signing in with that credential. To do so, call firebase.auth.Auth.fetchSignInMethodsForEmail, sign in to error.email via one of the providers returned and then firebase.User.linkWithCredential the original credential to that newly signed in user.
[[["Easy to understand","easyToUnderstand","thumb-up"],["Solved my problem","solvedMyProblem","thumb-up"],["Other","otherUp","thumb-up"]],[["Missing the information I need","missingTheInformationINeed","thumb-down"],["Too complicated / too many steps","tooComplicatedTooManySteps","thumb-down"],["Out of date","outOfDate","thumb-down"],["Samples / code issue","samplesCodeIssue","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2022-07-27 UTC."],[],[]]
Common Error Codes
error.email,error.phoneNumber, anderror.credential(firebase.auth.AuthCredential) may be provided, depending on the type of credential. You can recover from this error by signing in witherror.credentialdirectly via firebase.auth.Auth.signInWithCredential.error.emailanderror.credential(firebase.auth.AuthCredential) fields are also provided. You have to link the credential to the existing user with that email if you wish to continue signing in with that credential. To do so, call firebase.auth.Auth.fetchSignInMethodsForEmail, sign in toerror.emailvia one of the providers returned and then firebase.User.linkWithCredential the original credential to that newly signed in user.