Answer
You can reset your password, verify your email or change supported credentials through Account Management. If an entry is rejected, the form keeps your entries and shows feedback beside the field. “Check your email and password.” means either entry may need correction. Passwords keep the spaces and case you enter.
Correct the entries and retry. Connection problems, service errors and too many attempts appear in notifications. Going back from email/password sign-in restores the Google, Apple and email choices while keeping your entries.
For an invalid or expired recovery link, request a new link. A temporary connection failure may let you retry the same link. An email change already applied stays successful even if refreshing the account fails.