I had UK area divided into six different zones. I wanted to dissolve my feature class by zone just so I have six features in it. I used Dissolve tool which worked fine for five zones. One of the zones rather than being dissolved, got split into something that looks tiles.
I used the tool in ModelBuilder and also independently. And makes not difference if my output is stored in geodatabase or in the folder. I also run repair geometry on my input.
What would be the reason for that and how to make Dissolve tool work correctly?
Please see the image below.