Having seemingly random issue with gripper failing to close. After retrieving finished part using an ID hold, gripper sometimes fails to close and drop the part. Does not error, but instead continues with the UR program until it crashes trying to pick up a new part. After clearing the Protective Stop popup, gripper cannot be commanded closed. Activating gripper causes light to flash blue/red and clicking can be heard as if it is trying to move. Restarting the robot controller does not help. Prying the part off the gripper is the only way I have been able to activate and regain control of the gripper, but the same issue eventually returns if I run more parts. Any ideas on what may be causing this? Thanks in advance for any suggestions.