I met the same problem and recently I solved it with Leawo Contacts Recovery. You are able to take advantage of the third-party iPhone data recovery
software to get back the deleted contacts. Speaking of the iPhone contact recovery software, Leawo iOS Data Recovery stands out for its easy-to-use yet powerful feature. iPhone users can make full use of this software to recover deleted files from iPhone. The following guidance will introduce how to use it. Download Leawo iOS Data Recovery ' Leawo iOS Data Recovery for Mac
and install it.
Step 1 Connect your iPhone to the computer
Use a USB cable to connect your iPhone to the PC.
Step 2 Start to scan your iPhone
Once your device has been detected by the iPhone contacts recovery program, a "Start" interface will show, just click "Start" to scan your iPhone.
Step 3 Preview and choose contacts on iPhone
The scanning will only last for several minutes, after scanning, you are able to see all the different types of files listed in neat categories on the left sidebar. By clicking "Only display the deleted items" option on the left corner of the interface, you'll see all the files that have been deleted from your iPhone. Just click "Contacts" type to preview and then tick the single contacts you want to recover from iPhone.
Step 4 Recover deleted contacts on iPhone
After preview and selecting files, tap on "Recover" button on the right corner, then you'll see a pop-up window for you to choose saving location for the files. Click "Open" to browse the computer file explorer and choose a saving folder on your PC, then click "Go" to start to recover contacts from iPhone.
For more detail, check: How to Recover Deleted Contacts on iPhone