AirPods switching to another phone

After the recent update (14), my iPhone does not recognize my AirPods anymore. However, it recognizes my teenaged daughter’s phone. I’ll go through the trouble of pairing them, but if my daughter is close by and her Bluetooth is on,they will switch over to her phone. She disconnects, clicks on ignore the phone, but at a later point they’ll connect to her phone again. How can I stop this? It never used to happen before.