If it went directly to voicemail, the phone number might be accidentally blocked in your phone? Have you checked block list? Which phone are you using by the way.

I am using an iphone 7 and so is my wife. Her number is not blocked. I have several hundred blocked callers and none of these ever go to Voicemail. When her calls go to Voicemail they show up as Unknown Caller.

If the number was showed as "unknown caller", the caller likely disable the caller id in his/her phone. And the receiver likely blocked "unknown" contact in the phone .

If it was an iPhone, you can go to settings >> phone >> show my caller id >> turn it on. Also click on the option "silence unknown caller", turn if off. That might help

Thank you Dinh. My wife switched her phone to not show her caller ID last week. I have always used Sience unknown callers on my iphone. Switching her phone to show caller ID fixed the problem. Thanks Again.