so, i consider myself to have mild face blindness. if someone changes their hair or puts on glasses i will struggle to recognize them by their face alone (the Clark Kent/Superman effect - yes, i wouldn't recognize Superman is Clark Kent because of his change in appearance) i use style, mannerisms, voice, and a variety of other non-visual clues to recognize people when i worked retail i had to take mental notes about their appearance to be able to find them again.

I knew I had trouble recognizing faces long before I knew I had aphantasia. I always thought it was because maybe I was slow or maybe just wasn't paying attention. Just a few months after finding out I had aphantasia I saw my own son after not seeing him for 6 months. I stared at him for quite a while as his face seemed so foreign to me. He said "mom, you are staring at me being because you don't recognize me, aren't you?" I could have cried in shame. Then I could have cried with relief as I finally realized I may have an actual reason why I don't recognize people and it has nothing to do with being impolite.

I have the exact opposite, so much so that I seem to recognise almost everyone I have ever seen.  I once did an extensive set of online tests which afterwards suggested that I might be classified as a 'Super recogniser'.

I have the same problems, it's difficult. If the person has another hairstyle or anything else since the last meet, most of the time I let them greet me first.  If it's not to far away we met each other, I am able to regognize the person by his/her voice - but in the most cases without a name.  What learned to do, is to play the game "oh wow you're here, long time not seen" without trying to use a name. In over 90 % it works well and the other person did not realize that I can't remember him/her. Didn't found any other way yet to compensate this behavior.