I've used Turbotax for last several years and I just received notice that my 2020 state tax was never filed and they want to charge me $2,646.00 when in all reality I should have received a return
They didn't get your state return or a state tax due payment?
Maybe you didn't finish filing it or it Rejected. When you log into your account you should also see the status and if it was Accepted or Rejected, Started, Printed, Ready to Mail, etc. what does it say?
Then when you efile you get back 2 emails. The first email only confirms the transmission. The second email says if the IRS (or state) Accepte.d or Rejected your efile. Check back though your emails if you have them.
Or if you mailed your returns you had to mail federal and state in separate envelopes to different places. Maybe the state got mailed with your federal return.
If the state didn't get it you will have to print and mail it now. How to Access prior year online returns
If you can't get the side menus to open up to access the prior year..... You need to start entering some basic Personal Info in 2021 for the side menu to open up. Just continue a little ways into 2021.
If you used the Desktop CD/Download program then the only copy is on your computer and not saved or stored online. So you need to make and keep your own backups.