I have an iPhone 13 with the latest release of iOS 17. Back in October, I recorded a new personal greeting announcing that I was out on vacation for a week.
I've tried several times since then to record a new personal greeting without the vacation message, and although it records and then plays correctly when I listen to it, if someone calls my phone and I don't answer, they get the old "vacation" greeting. Even if I go to "Personal options -> personal greeting", it plays the new one. But callers get the old one.
I've never had this issue before.