Speed dialing entry stopped working

On my land line, 2 days ago, I successfully entered 8 speed dial numbers. Yesterday I tried to enter another 8. The first 5 worked. Then I got the message "We're sorry. The system can not process this service at this time. Please try later." I tried later last night, and several times today. Same thing. Impossible to reach anyone for a chat or call with a real person. I'm so frustrated. Just want to know what is going on, and when I can enter more numbers. Verizon customer support is terrible! No support at all!