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: Account Access and Safety
: Other mobile device (please specify)
It might help if you can explain how you locked yourself out of the YouTube account in the first place?
Did you forget the password? Did you forget the username?
You then explain trying to link your YouTube to a newer GMail account - if your YouTube account was started prior to 2009, this should have been perfectly possible and quite straightforward. See the reference below - is that what you did?
If so, you should now sign in to YouTube with the ID and password you use for the GMail account, because your old YouTube password will no longer work. Have you tried that?