One option is to approve on her device directly.
From: Approve what kids buy with Ask to Buy - Apple Support
See the section below for how to get approval in person.
How children or teens can make a request with Ask to Buy
1. To buy or download an item, tap the price or Get button. Or if you're using an Apple Watch, double-click the side button, then enter your passcode.
2. If asked, enter your Apple ID and password.
3. Tap Ask. If your parent or guardian is nearby, you can tap "approve it in person" and they can approve the purchase directly from your device.
4. After your parent or guardian buys the item, it downloads to your device automatically.
The account management features for the Android interface are very limited. You would have to ask Apple if there is a way for you to disable Ask To Buy.
Refer to this document for ways to contact Apple ➞ Choose your country or region - Official Apple Support
Select your country (also look for "other" regions), then a product. If you don't see one that handles your issue then keep experimenting with selections until you reach one that gets you a chat session or a telephone call and get the representative to redirect you.
or:
Contact Apple for support and service by telephone ➞ Contact Apple for support and service - Apple Support
for "Billing and subscriptions" support, click here --> Subscriptions and Billing - Official Apple Support