Your iPhone can now send spam calls directly to voicemail — here's how to set it up. But, if your iPhone thinks it knows the number — like if you've called someone who isn't in your phone In one instance, for example, I had this turned on and my colleague's calls kept going right to my voicemail.
To set up voicemail on your iPhone 12, you must make sure to check carrier supports Visual Voicemail. If it does, follow the steps below:

This article is about the second main type of greeting – the voicemail greeting. All businesses should have professional voicemail greetings at the company level (i.e. your general business number), department level (e.g. customer service), and employee level, where applicable. It’s important that each of these voicemail greetings align with the brand and personality of your company to ensure that every caller has a consistent experience. Let’s dive in!
Activating voicemail on an Android phone 1. Turn on the power for your phone and open the Phone app. Turn your phone on and tap the Phone app, as if you were going to call a person. 2. Open the dial pad so that you can enter your voicemail system's number. Next, tap the dial pad icon in the bottom-middle of the screen. 3. Call your voicemail