I had a similar problem and my troubleshooting was:
1 - go to the 'data' tab on the property editor of the uitable
2 - check the 'Do not set value and leave table empty'
3 - go back to the 'columns' tab and add/delete/etc
(4) - go back to the 'data' tab and adjust to whichever data is necessary to be there
Hope this helps!