Identifying amended return discrepancy

[RMenschel]

I filed 2020 return "accurately" using all information available to me, using TurboTax (windows desktop). After receiving my refund, long after the 1099 deadline, I received a 1099-NEC from Postmates. I used TurboTax to generate an amended return. TurboTax told me I owed $202, which I paid. 

I've now finally received a letter from IRS indicating that I should have paid $212. They want the $10, plus interest. 

Pulling my Record of Account from the IRS website, I find code 767, Reduced or removed credit to your account of $65, and code 765, Reduced or removed earned income credit $147. These together add u to the $212. My amended return shows $137 reduction in EIC, so that's where the $10 discrepancy comes from. 

Is there any way to determine why TurboTax calculated an EIC adjustment different from what the IRS calculated? 

[RobertB4444]

Not with this amount of information there isn't.

It is possible that the IRS is wrong and the EIC should have been reduced $137 instead of $147.  In fact that seems most likely.  But the argument with the IRS isn't really worth ten bucks and they know it.