I'm using desktop deluxe, windows 10. this works in my version for line 1a 1099-DIV and line 3 of 1099-INT- (data imported) right-click in the box, then scroll down to add supporting detail. That should open a window to input your details. If not, maybe delete the 0.00 amount. Also, try on other lines. If it works it may be that if you imported, the app is blocking you from changing those numbers. you could remove selected imported data from the file tab. Then retry. Last resort manual entry.
