Hi teona227,
Thanks for posting in Apple Support Communities. Since you are moving from Android to iPhone, you're on the right track with the Move to iOS app. The guidance in Move from Android to iPhone, iPad, or iPod touch - Apple Support has details that might help including the following from the 'If you need help with the transfer' section.
If you need help with the transfer
• Make sure that you leave both devices alone until the transfer finishes. For example, on your Android device, the Move to iOS app should stay onscreen the whole time. If you use another app or get a phone call on your Android before the transfer finishes, your content won't transfer.
• On your Android device, turn off apps or settings that might affect your Wi-Fi connection, like the Sprint Connections Optimizer or the Smart Network Switch. Then find Wi-Fi in Settings, touch and hold each known network, and forget the network. Then try the transfer again.
• Restart both of your devices and try again.
• On your Android device, turn off your cellular data connection. Then try the transfer again.
Since it also sounds like the issue might impact WhatsApp in particular and not other data, we'd also recommend checking out the following page from the app developer - How to migrate your WhatsApp data from Android to iPhone.
Best of luck.