SSRS not letting me change dataset of a table

Question

I have a report with a table in it. I need to change the dataset that this table uses. When I go the tablix properties and try to change the DataSetName, it automatically gets reverted back to the original dataset instead of the new one I selected.

Any ideas on how to fix it and why it's happening?

Answer 1

I figured it out. Turns out that the entire report was inside a table with one gigantic column. That column had a rectangle which contained the entire report. So obviously my table kept inheriting the datasource from the root table. I took out the needless "root" table and rectangle, and the report now works as desired. Thanks guys for trying to help, much appreciated :)