This error is returned when the credentials provided by the user to Link are invalid.
To resolve this, please confirm the user is selecting the correct institution in Link and entering the correct credentials. The user can confirm their credentials are correct by logging directly into their account at their institution’s website.
If the user is using a password manager or something that automatically fills out the password field, they should try to either view what is being entered or enter it manually so they can verify the credentials. If they then enter those same credentials when connecting through Plaid they should be able to connect.