Who I have the same questioned this topic

I have two friends that just got new US cellular Cell phones and now i cant call them, they can call me. the error says that all circuts are busy, please try your call again, annoucement: 8,Switch 150-1.. what is this?

Why is this happening? they got new phones, and I had no issues calling them prior to them getting new phones, but when they take their phones to US cellular, they are told that their phones are fine and the issues is in the Verizon phones. Is this possible? had issues like this? So far these two individuals have identified that they cant receive phone calls from myself and 3 other Verizon customers. But I can text him and he can contact me via phone call.

I tried calling their numbers from my Work Cell phone which is also Verizon, can I get the same issue.

any help would be great. Thanks, Nate