To repair a cavitating elevator, the techs come in and add oil. Literally. That's it, and then they ride it a few times to make sure that it shuts up.

However, the phone operators are especially trained to handle entrapments. They will talk to you if you have anxiety, they will keep you calm, and, if you have a medical emergency, they will call EMTs. So yes, trust in the button.

They gotchu.