If you have enabled iCloud on your iPhone, please turn it off temporarily by going to Settings > iCloud > turn off Contacts > select Keep on My iPhone, Then use FonePaw iOS Transfer to scan only your Contacts.
If the problem still persists, contact us with the following information:
1) What is your iTunes version? Can iTunes detect your iPhone?
2) What is your device and iOS?
3) What is the OS of your computer?
4) Send us the screenshot of FonePaw iOS Transfer.
5) Submit the log file through feedback section on the upper right corner of FonePaw iOS Transfer.