Pairing old Kirkland hearing aids with new iPhone14

I have older hearing aids that work just fine. They are Costco Kirkland aids, circa 2017. I have always had them paired to my iPhones with the KS6 app. Today I got an iPhone14 and I cannot pair it with these aids. (They still connect fine to the old phone & play podcasts if its Bluetooth is on. Turned it off to avoid conflict. The new iPhone pairs with my spouse's AirPods, so not the phone per se).

I had not anticipated this and am not sure what to do now? Throw away the KS6 app and try the newer KS10 app? Buy new $$$ aids? Take the phone back? Any experience with this situation would be warmly received. Thanks in advance.