Use the "Delete a Form" tool to
remove the Form 1116: Foreign Tax Credit (and any
associated worksheets), then re-enter the information in the Foreign Tax Credit interview.
See: How do I delete forms in TurboTax Online?
After
deleting Form 1116: Foreign Tax Credit (and any associated worksheets). log out of the program. When you
log back in, use the Delete a Form tool (List of Forms in My Return) to confirm
they have been removed from your return. Then go back to the Foreign Tax Credit interview and make the correct entries.
Why does this happen? Once you enter (or import
or transfer) certain information, the program creates or updates forms and
worksheets that use that information. In many cases, you cannot
"change" that information in the interview process - in a manner of
speaking, it has been "written in ink" on the forms. You have to
delete the form and any associated worksheets in order to correct.