Everyone can call my mom's phone except me, I am not blocked

Hello bproskine, I'm sorry to hear that you're experiencing difficulty calling your mom on your iPhone 12 Pro Max.

Let's work together to resolve this issue. Here are some steps you can take:

1. Check Network Connection: Ensure that your iPhone is connected to a stable network, either Wi-Fi or cellular data. You can verify this by opening a web page or using an app that requires internet access.
2. Restart your iPhone: Sometimes, a simple restart can fix various issues. Please press and hold the power button until you see the "slide to power off" option. Slide to power off, wait a few seconds, then press and hold the power button again to turn it back on.
3. Update iOS: It's important to keep your iPhone's software up to date. Check for any available updates by going to Settings > General > Software Update. If an update is available, download and install it.
4. Reset Network Settings: If the problem persists, you can try resetting your iPhone's network settings. Navigate to Settings > General > Reset > Reset Network Settings. Keep in mind that this will erase Wi-Fi networks and passwords, cellular settings, and VPN configurations. You'll need to re-enter Wi-Fi passwords afterward.
5. Check Blocked Contacts: Although your mom may not have blocked you, it's worth checking your iPhone's blocked contacts list. Go to Settings > Phone > Blocked Contacts and ensure that her number is not listed there. If it is, remove it.
6. Contact Apple Support: If none of the above steps resolve the issue, please reach out to Apple Support for further assistance. They can provide additional troubleshooting steps tailored to your situation and determine if there's a hardware-related concern with your iPhone.