the return was due 3/16/2020. it is 4 months late. the penalty for filing late is $195/per month late/per shareholder. are you sure the notice isn't a bill for the late filing? if it is you can write back with the notice and request abatement of the penalties due to your confusion over the due date and also state that steps have been taken to prevent future late filings. the IRS will make the final decision about the penalty abatement. if it's anything else.
you'll have to contact TT support because this is a public forum that has no access to any of your records.
or call the number on the notice for clarification. usually the IRS will issue a seizure notice only after other notices are ignored.
Contact Customer Service
5am-5pm Pacific Time (8-8 Eastern) Monday - Friday
https://support.turbotax.intuit.com/contact
