To access your previous year's tax return you will need to upgrade to TT Plus. Please see the necessary steps below:
https://ttlc.intuit.com/replies/3301525
You may also try the steps below:
1.Sign in to your account
2.Go to Help, select Contact us, type in Add PLUS Benefits, and
3.Follow the on-screen instructions to add PLUS and pay.
If for some reason you are not seeing the 'upgrade' button; please see the tips in the link below.
https://ttlc.intuit.com/questions/2896514-why-don-t-i-see-the-upgrade-option-in-turbotax-online
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