First, welcome to the Mendix community! Did you replace the default Cancel button with an own Action button to call a microflow? In that case, you could add the "Rollback" activity in that microflow. Did you use On Change microflows, for example at the dropdown? Did you commit inside those?
Hopefully this helps a bit.
Kind regards, Johan
Seems that you do have an on change event on the drop down which commits the object. Check in your widget properties the on change event.
Thanks Johan and Rene,
This works! I am no more getting on change problem, 1- Removed the required validation from the drop down as this is taken care in Microflow. 2- Added the roll back in the cancel microflow.
However when i change a Drop down(with no events or validation) and Click the Cancel Button(X) its gets saved and refreshed in the main page.