Entered wrong numbers for 2020 IRA contribution, how to amend?

Hi all,

My wife and I did backdoor Roth conversions in 2020.  I believe we entered the 1099-R numbers (amount converted) TurboTax on 8606 form instead of our nondeductible contributions.  We also recharacterized some of this contribution in 2021, for year 2020 so TurboTax is asking us to amend it.  

My question is, when I amend 2020, can we fix the wrong contribution entered wrong from 2020 as well as add our recharacterization at the same time?  After we fix it, can we send it in paper or electronic?  How long do I have to wait after I submit the amendment can I finish our 2021 return, or do we have to wait for a response?  


do we have to amend 2020 before moving forward with our 2021 return?

We have never amended anything.  Thank you