Is there a way I can check online with the IRS if an extension has been filed and accepted for my taxes?

I'm doing my mother's taxes and they were previously done by an accountant. I filed an Easy Extension through TurboTax and it got rejected saying the Taxpayer TIN in the return header must not be the same as a previously accepted electronic return.... So I was wondering if the accountant automatically filed an extension since they haven't gotten any info from me.