Sometimes there may be characters in the boxes that we cannot see. Sort of a computer issue.
Make sure you go back to the original 1099-DIV entry and not trying to correct as an error. If it gets corrected on the original 1099-DIV, the error will disappear.
Try clicking on the Payer box and deleting. Making sure that you are deleting seen and unseen characters.
Also, the important thing is the tax identification number for the Payer. Some of the Payer names are rather long so it's ok to shorten it as long as the tax identification number is correct and the name is at least a semblance of what it should be.
If this doesn't work, please let me know.
