Cannot merge account

I have 2 account with different emails, 1rst acc linked to steam 2d account is xbox account in the first place I have created for him different email and when I on the 1rst acc clicking into connect to "Microsoft" this error occur.

Can I connect me only 1rst acc to 2, or I can do it in reverse?

You cannot add this login method to this account.

You cannot merge two accounts with the same login methods