This FAQ lists a few reasons you might not be able to find the TurboTax Online return you’re looking for: https://turbotax.community.intuit.ca/community/importing-transfering/help/why-can-t-i-find-my-turbot...

I checked both user IDs and still cant find my un-efiled returns. I was going to file them then but it was before the opening date for e-filing with the CRA. Any way to retrieve these returns?

Unfortunately, If your returns are no longer in your account, you will need to start them over again.