Cannot call my child on their Apple Watch SE

Does anyone have issues calling their child on their Apple Watch SE? They do not have an iPhone and I am the Family Sharing organizer and set up the watch for them on my phone. They have their own Apple ID. We got the watch two days ago. All devices are up to date on system updates: My phone, their watch and also their iPad which is also connected to Family Sharing.

My husband, who is also included on family sharing can call them with no issues. I manage their contacts and am in their contacts. I can call them from my work phone, which is separate from my personal phone but is also in their contacts. When I try to call from my personal phone, which is the phone that I manage family sharing from, the call goes straight to voice mail. I can text them from my personal phone though.

I was on a support call with Apple this morning and was disconnected. When the person called back I accepted the call and then it disconnected again...no call back from them. How do I remedy this?