... Then look on the menu, which, if you have everything set at default, should be on the left side. Look for "Linked IDs" and click that.
You should then be on the linked IDs management page. Your IDs should be listed there. Just click "unlink" next to the ID you don't want linked anymore.
That should do it. If not, please respond with more detailed information.
Here is the official word from Microsoft if you want to look around the live help zone:
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