Changing password Verify with old password, verify by email, or don't verify?

1. Why does Google ask for old password?
2. Why does Google keep asking me to verify my account?
3. Why can't I verify my Google account?

Why does Google ask for old password?

If there's suspicious activity in your Google Account or we detect that your password has been stolen, we may ask you to change your password. By changing your password, you help make sure that only you can use your account.

Why does Google keep asking me to verify my account?

To help protect you from abuse, we sometimes ask you to prove you're not a robot before you can create or sign in to your account. This extra confirmation by phone helps keep spammers to abuse our systems.

Why can't I verify my Google account?

Important: If you can't verify it's you, Google may not allow you to complete the sensitive action for a period of 7 days. This delay is to make sure your account and data stay protected.