I can't buy Mincraft for MS family child: stuck on "Hold on It looks like your parent approved this. Check with them in a bit"

I want to buy and install Minecraft on Windows 10 for my daughter. She is a daughter in my MS family.
 
When she clicks buy on minecraft.net she gets this error:
"Hold on It looks like your parent approved this. Check with them in a bit"
 
I see NO alert to buy the app. No email. No alert in account.microsoft.com/profile or in family app.
 
I look back at a 3 month old email, asking for permission, and when I click allow it says:
"This purchase request has expired. To purchase the product again, ask your family member to make this purchase request again."
I think maybe I previously approved it months ago but didn't pay for it.
 
But when we follow the instructions and "ask your family member to make this purchase request again", it does not change this error, and I still don't get any notifications anywhere.
 
As I understand it, there is a bug in the microsoft system somewhere: If a child asks to buy Minecraft, it sends a message to the parent with a question if the approve and a link of how to pay. If the parent approves it, but does not pay immediately, but comes back later, that payment link has now expired and has no option to renew the payment link (which if bug #1).
Then if the child tries to buy again later they fall into bug #2 which is that the microsoft system sees the parent has approved it so tells the child "Hold on It looks like your parent approved this. Check with them in a bit". BUT the microsoft system NEVER sends a new message to the parent with a new payment link.