iOS Does Not See Devices

[arretx]

*** Posting again because the previous post just disappeared ***

1 MacBook Air

2 iPhone 7 phones.

One phone can see the MacBook when Spotify is open, one cannot.  This happened when we both had iPhone 6 phones recently.  It's not a phone thing, it's an account thing.  We're on a premium family account, on the same network, on the same everything.

How do we fix this?  I've been through every post I can find and almost every one of them has the same solution that doesn't work.

[arretx]

I've cleare caches, I've soft rebooted, I've uninstalled and re-installed, I've logged out and logged in and I've tried another WIFI network. Nothing changes.

The only thing different about the accounts is that one was setup using Facebook Connect and the other was added as a family account later using a username and password.

???  What ??? do ??? we ??? do ???