It’s part of the kyc procedure, it is required so that the app can be a wallet
Why does nostr:npub12vkcxr0luzwp8e673v29eqjhrr7p9vqq8asav85swaepclllj09sylpugg require my name and email address to create a lightning wallet? 
Discussion
Consider adding a brief explanation on that screen describing why you are asking for this information. Lightning and Nostr don’t require or use name and email in their protocols.