One of the best and quick fix to this issue is to turn off Wi-Fi for once and switch to Cellular data connection and then try to change the default greeting to custom on iPhone.
Unexpected crises like COVID-19 can occur at any time. Here are a few example business voicemail scripts you can adapt for those unanticipated events. It’s important to incorporate key information that your clients need to know. You should also add a human touch by expressing your goodwill for them and their families.

Informal voicemail greetings are those that don’t adhere to the rules of professional and business voicemail greetings. Here, you are free to just leave a simple greeting, or use it to show your more witty side. This style of greetings can be used for both home and business if you like, depending on the type of caller you expect. For instance, a novelty shop could probably create a rather informal message, using sound effects that represent the type of items they sell.
Here, the oncologist is busy consulting a patient, but he/she leaves ways for the callers to fulfill their needs right away. A lawyer’s office needs to maintain professionalism at all times in order to record the perfect voicemail greeting. Let’s look at an voicemail greeting script example.