There are several postings regarding that issue and appears to be a flaw for TY2018. Try the following work around.
Bring up the 1099-DIV and in Box 7, double click on that f1116 icon. Another box will appear. You will see the phrase "Form 1116 (COPY 1). Click on that and it will be highlighted. Then click on the "Link" button. That box will disappear and you should see the phrase "COPY 1" inside the f1116 icon in the 1099-DIV, box 7.
Then recheck line 48 of the 1040 to make sure you still have the credit. If so, that should remove the error.
