Boyfriend claims that two messages I found on IMessage to ex are showing as the wrong date

Today, I stumbled upon messages between my boyfriend (we’ve been together for seven years) and a girl he was involved with within months of us getting together in those seven years. The two messages were sent on Jan 4th and then Jan 12th. The messages also showed that it was read by her on 1/12/24. When I confronted him, he claimed that his iPhone sometimes messes up the dates when he sends text.I know it sounds like a weak excuse, and I feel foolish for even considering it, but has this ever happened to anyone else?