I need to re-enter my SIN number as turbotax has saved my old one. Everytime I try to edit and save my new one, the old one saves and so I can't file my return

[TurboTaxGinette]

If you are auto transferring last year's information at the beginning of your return then all the past name, address, SIN, etc. is coming back. You may need to start a fresh return without transferring last year's information. After you start fresh this year, you will be able to transfer from the correct information next year. 

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