There have have been several Roku "2" models over the years. A few are no longer supported. Roku hasn't used link codes in years, so the fact that yours is displaying one is an indication that it's no longer supported and can't be linked to a Roku account anymore. Sorry.
You can see if yours is on this list under "Legacy models".
Hardware specifications | Roku Developer
By the way, the "trclink" URL is to link The Roku Channel to a Roku account and isn't the same as linking a Roku device to a Roku account.
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