Fully charged airpod quit after 10 minutes

My husband has gone through 3 sets of airpods that work fine for 2 months then one of them stops working 10 minutes into his walk. This has happened 3 times with 3 different sets of AirPods, even the latest pro version. He has an iPhone 13 mini. We have checked the charging which is fine. They are both charged. He reboots the phone but it doesn’t help. Is this a problem with the iPhone 13 mini?