This may be a fault for more than Excel in the Office Suite but at this time my email (Thunderbird) is working perfectly.

In EXCEL I type in a cell - works fine. Press enter or scroll down to the next cell. New typing will not appear in that cell. Click to the next sheet and new typing will appear as expected. Click back to the first sheet and new typing will appear in the active cell as expected. Press enter or scroll down to the next cell. New typing will not appear in that cell. And this problem can be repeated endlessly.

My attempt to fix this so far has been to totally re-install Microsoft Office. No fix and one loss in that Office is no longer visible in the All Apps list.