Turbotax is not licensed for use by professionals. If the CPA used the personal version of turbotax installed on their own computer, Turbotax does not have copies of your returns. You can get transcripts from the IRS. https://www.irs.gov/individuals/get-transcript
If the CPA used Turbotax Online, it might be possible to get that account reassigned to you, but you will have to fax in proof of your identity.
If the CPA used one of Intuit's professional products, you probably won't be able to get anything from the support phone number and will have to get your transcripts from the IRS.
Use the contact form to get a customer support number.
https://support.turbotax.intuit.com/contact/
