Hello Njariri,
Welcome to Apple Support Communities!
We can help get your Samsung data switched over to your new device.
Let's make sure you're ready to start after taking these steps:
"Before you begin
- On your Android device, make sure that Wi‑Fi is turned on.
- Plug your new iOS device and your Android device into power.
- Make sure that the content you're moving, including what's on your external Micro SD card, will fit on your new iOS device
- If you want to transfer your Chrome bookmarks, update to the latest version of Chrome on your Android device."
This Apple Support page has the full details and next steps to take: Move from Android to iPhone, iPad, or iPod touch - Apple Support
If the issue continues, try restarting both devices and then trying again.
We hope this helps to get your data moved over via Android File Transfer to resolve the issue.
Cheers!