I encountered something similar in that match - and by chance I was able to replicate it because I accidentally closed the app before it saved after winning the match.

In the first match, the AI played the following series of enchantments, across two turns, on the first creature I played (even after both I and it had other creatures on the field):
1. Knight's Pledge (+2/+2)
2. Another Knight's Pledge
3. Pacify (can't attack or block)
In that order. Then I Unsummoned my card, and it played a Knight's Pledge on the first creature it had played, followed by Pacify on that same creature.

When I played the match the second time, I didn't Unsummon my creature just to see what would happen, and it played the exact same sequence of cards all on my creature. Seems like maybe the targeting is "stuck" on always targeting the creature that has been on the battlefield the longest?

When I played the next match, Blue vs Red, I also encountered something similar, though less extreme: the AI played a card that let it take control of another creature on a creature that it already controlled, twice. (I think that creature may have also been on the battlefield the longest at that point, but I'm not completely certain.)