Adresse bizarre

Bonjour,
lorsque je veux consulter ma messagerie et que je dois taper mon identification,je trouve en plus de mon adresse mail ,une aute adresse que voici,

[email protected]

mais cette adresse n existe pas ??

This is the mail system at host msfrf1101.sfr.fr.

I'm sorry to have to inform you that your message could not
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The mail system

<[email protected]>: host f.mx.mail.yahoo.com[98.137.54.237] said: 554
delivery error: dd This user doesn't have a yahoo.fr account
([email protected]) [0] - mta143.mail.sp2.yahoo.com (in reply to end
of DATA command)

voilà ce que je reçois si j envoie un mail ?
qui peut me renseigner ?
Merci

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