Using this to reply to both the OP and a comment you mentioned Facebook in.
- I'll start with the Facebook thing- even though your Facebook email and OSRS email might be the same, we don't know that. We don't know what your Facebook login credentials are, it's not how account linking works when you use social platform logins. Rather than the system saying "Oh, it's ***@***.com's Facebook account" it says "This is Facebook account xyz". You've essentially just created a brand new Old School account using your Facebook.
- The actual issue with your email. Without seeing your account I'm unsure why it was locked, but it's clear you have access to the email, so you can simply unlock it by following these instructions: https://support.runescape.com/hc/en-gb/articles/206103939-My-account-is-locked (hit the Unlock Account button)
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