To set Mediacom Mobile as your default line on iOS, follow these steps:

1. From your Home screen, go to Settings > Cellular.
2. If you can’t find the Settings app on your Home screen, swipe left to access the App Library.
3.  Tap “Default Voice Line.”
4. Note: This option is available only when using Dual SIM.
5.  Tap “Default Voice Line” again.
6.  Choose the Mediacom Mobile line (e.g., Account owner, Additional, etc.).
7. The selected line will have a checkmark next to it.

These steps will set Mediacom Mobile as your default line on iOS.