Try this:  Delete the substitute 1099-R and enter it as "Other Income."  (Instructions are below.)  The end tax result (in terms of United States tax rate and amount assessed) will be identical to the results achieved with the substitute 1099-R.

To enter your foreign pension on your return, follow the instructions below:

• Choose the Federal return and the Wages & Income tab.
• Scroll down to Less Common Income and Show more.
• Choose Miscellaneous Income, 1099-A, 1099-C.
• Choose Other Reportable Income and say Yes.
• Even though the screen says "Do not enter income reported on Form 1099-MISC", this is where you will enter the description "Foreign Pension" the amount you received, and who received it, if necessary.

OK, but where do I put the tax that was withheld by the foreign government on my pension?

@Filippo61 You can file Form 1116 to get a Tax Credit for Foreign Tax Paid.

Click this link for info on How to enter Form 1116.