Unable to join wifi network.

Have been connecting to my home network fine for years. I have:

1. turned phone off and on
2. reset router
3. checked to be sure wifi was on on iphone
4. on iOS 15.6.1 on iPhone 13 pro max

The message that comes up says: Unable to join wifi network. This network is operating on Wi-Fi channels in use by several other nearby networks. Restarting your wireless router may allow it to automatically choose the best channel to use, and may resolve this problem.

my daughters iPad hasn’t been updated to the new iOS and hers connects just fine. My husband and I have updated and neither our iPads or iPhones connect anymore.