Nowadays, there are many transmission shafts in cars without nozzles, which is what manufacturers call maintenance-free cross shafts. This universal joint doesn't need to be buttered, so it can't be played. If it is broken, it can only be replaced.
The universal joint is a choke, which falls off due to insufficient tightness during driving. If you see that this universal joint has a hole, but there is no nozzle, you just need to buy a new nozzle and replace it.