Email Address associated with Microsoft Account migrated over to new system

Hi,

I have a customer that created a form last year. They want to re-use this form this year. When they log in to Microsoft Forms the form is no longer available. In the past year, the email address that is associated with their Microsoft account has been migrated over to a new system. Would this have affected the Forms that had previously been created before the migration? They can only access forms that they have created since the migration took place.

Thanks,

Nick