@mongo19696 , Don, Try to find the phone app clear cache then erase data and press OK, then try to make a call. If this does not do it, possibility other App/software could be corrupt and a Hard reset may solve the issue. Hard Reset will erase all of your data. 1st link is more trouble shooting info. for you to check out and th 2nd link pick your device to see how to perform Hard reset. Good luck. I hope this helped you out, if so let me know by pressing the helpful button.
http://devicehelp.boostmobile.com/document/troubleshooting/Speed/Boost_Mobile/en/Troubleshoot_when_your_ZTE_Speed_slows__freezes__or_turns_off_unexpectedly/