use SaveMii

Doesn't work... Nintendo Land uses shared game data between users. I can't import data from a Mii to another Mii unless a save editor for Nintendo Land exists.

Delete the mii you used for before then press yourself to see stats. There should be a button to see others stats and then you should see a mii which is your deleted mii. This happened to me once. Hope it works if you see this. ♥♥