Two of mine were missing when i bought mine. The design is not robust especially for our Canadian winters. The opening surrounding the actual nozzle splits from the cold and the nozzle, which is a friction fit, simply pops out when you use the squirter.
Here is an olde thread covering a lot about these.
Headlamp washer nozzles
I ended up going the BMW part route and actually gluing them into the openings. That was 2 years ago and so far so good. I avoid using the squirter if I can.