Brawl Stars-How do I disable or enable in-app purchases?-[English]

Supercell games are free to play, but you can buy in-game currency to progress faster. In-game currency is purchased with real money using either Google or iTunes.
To set restrictions on your device, please refer to the link:
For Google
For Apple
If you’d like to continue making in-app purchases, set the device to require your password every time you make a purchase (select “Immediately”) or every fifteen minutes.