Deferral of self-employed taxes ~ IRS claims different amount than tax return

[cmorristax]

On line 12(e) of Schedule 3 of my 2020 return, my tax return says I owe Uncle Sam $1,813 for the deferral of self-employment taxes, half of this being due on Dec 31, 2021, and the other half due on Dec 31, 2022. I received a letter from the IRS that says I owe them $1,013 on Dec 31, 2021. Why are the numbers different, and what amount should I pay?

[Critter-3]

Did you file an amended return and reduce your Sch C income ?  If so that could be the difference since the amended return has most likely not been processed yet.  

Contact the IRS using the number on the notice and ask why the amounts are different.  

[cmorristax]

I did not file an amended return. I will call the IRS.