I'm seeing a similar error. At first I thought the 1116 form was missing either the foreign-income source country or the date when the foreign taxes were paid. I compared my 2019 return against the current 2020 return. All required fields are exactly the same. I'm lost and very frustrated.

ERROR MESSAGE:

We walked through the exact same form Q&A process Let's take a look at your return Description of error: We encountered an issue processing your e-filed return. Please review the "ForeignTaxesPaidOrAccruedDt" on Form "1116" in the section "ForeignTaxCreditSource". What needs to be done: There was an issue with the submission of this return. To correct, navigate to the Deductions & Credits Tab, under the Menu heading Estimates and Other Taxes Paid choose Foreign Tax Credit. Proceed to answer all the question in the topic. After this, in the Review Tab verify that you have cleared any error messages that are present in the return and resubmit this filing. If you continue to have issues with submission of this filing you can choose to file using US Mail.