wd my passport pro and macbook 2017 - how to connect?

I have a WD My Passport Pro external drive that I used with my old MacBook Air. I now have a 2017 MacBook that only has the one port. I purchased an official Apple Thunderbolt 3 (USB-C) to Thunderbolt 2 Adapter and if fits physically. However, when I connect I get a "Cannot Use Thunderbolt Accessory" error message and I cannot see the external drive. Is there a solution to this? If not, any suggestions on how I transfer all of my data from the external drive (all of my photos and much more).