Ottocast wireless adapter problem

Iphone: 15Pro Max

I am using an Ottocast wireless adapter in a 2020 Lexus LS500. The device works well for Carplay infotainment and allows me to make cell phone calls using the car's display from a group of saved contacts.

When I tried to use the native Lexus telephone voice control, I get an "attach a phone and try again, error message". If I try to reinstall my cellphone with the Ottocast plugged in, the car does not display the Bluetooth option.

Unplugging the Ottocast wireless adapter allows me to reinstall my cell phone.

I have reached out to Ottocast without success.

Is there a solution to this problem?