Isaac Sim gripper going through object

When I’m using Isaac Sim to model a gripper closing around an object (I used a cylinder shape with “Rigid Body with Colliders Preset”), the gripper seems to close around the object, but then glitches a bit, and then goes through the object. I imported the gripper with the URDF Importer tool, and checked that the gripper has a collider mesh around it.
What can I do to make the gripper able to pick up the object?