I have been trying to solve this for ages. I tried reinstalling the app on my phone and on my PC. I updated my phone. I looked at ways to alter the keyboard because I was getting an 8 digit alphanumeric code. Nothing worked.
SOLVED - SOLUTION - 9 Number Pin - Phone Link
Then I decided to Google for an install of Phone Link and found this one: https://www.techspot.com/downloads/3660-phone-link-app.html
I ran the install and it gave me a warning "You already have a newer version installed" but I clicked "Install Anyway" and it overwrote the updated version. Then I tried to link it again and it finally gave me a 9 code pin in the format of 012-345-678 and I was able to pair the dang phone.
It took me a while to sort out the Bluetooth after this, so that I could make calls. I fixed it my deleting the paired PC from my phone and phone from my PC and then tried again and it finally linked and gave me full functionality.
Just leaving this reply here because it might help someone else in the future!
<3