Here's some advice, taken from personal experience. YMMV.

Treat them like people. Ask them their name, feel free to chat with them a tiny bit, anything to lessen the monotony of their day. You'll find you often get a much more engaged and helpful response as a result, because surprisingly, bored people don't tend to function well.

Obviously, this won't work all the time (people are different and there are always idiots), but I've had pretty good success with it over numerous fields (banks, tech support, sales, ...) and it usually makes *me* a lot more happier to try make an effort to connect with another human being rather than interfacing with a 'faceless drone'.

(Having been on the other side of the phone some years ago, I can also say that things like this are appreciated. A lot.)