Which phone model are you using? If other incoming calls were ok, you might have either blocked the number or blocked "unknown calls" in your phone. I suggest you check if that was the case.

I’m using a LG61. I’ll try checking that but as stated in the original description, I feel pretty confident there was no phone configuration changed between when those calls used to work normally and yesterday when those calls were now going to voice mail.

Thanks!

Confirming my call settings are not manipulating that number any differently.

Can you recheck if you block unknown calls? I recalled some numbers in the hospital have their number "hidden". 

Also, did it happen only once or many times? Sometimes, it could be just a glitch somewhere either at the phone or network. 

I also assumed you didn't accidentally turn on "do not disturb mode" at that time?

Rechecked and only 1 number was blocked and it wasn’t the number that brought this concern.

It happens several times yesterday on November 23rd.

The “do not disturb mode” had not been turned on.

Thanks!

The same call that didn’t come through on Wednesday came through on my phone yesterday so I consider this “done” for now.