One thing I’ve learned is that if you use the Filter, it does not update the State of the robot, so you need to click the Refresh button on right side or turn off Filter. Maybe it actually stopped but it just doesn’t look like it.
Another thing to consider is if you chose “Stop” instead of “Kill” because Stop will run the rest of the process until it hits the Should Stop and a condition that tells your process to branch to a closure sequence. If you don’t have that condition it will still try to finish the complete job.
Another thing, but probably unlikely, is that your server’s performance is just really slow. Maybe it is linked to the SQL server or the Orchestrator installation was faulty. If this is the case, I’m not sure what the solution could be other than working with UiPath support.