The ring has a C shaped band so it can come off the finger easily
He likes to fidget with it as can be seen here.
So I believe that's the explanation of it.
As for AI: modern phone cameras rely heavily on algorithms and AI to enhance images, often introducing artificial effects and unintended artifacts... so that could also be happening in this clip.
I don't think this clip is important enough right now to figure out exactly how the ring moves like that....