iPhone 15 Pro Max disconnects from Bluetooth headphones with incoming calls

I have played with the settings at Settings > Accessibility > Touch > Call Audio Routing -- switching from Automatic to Bluetooth Headset and Speaker and back to Automatic and restarted the phone multiple times but the problem persists - when setting is Automatic and I am listening to audio with Bluetooth earphones and a call comes in the audio is routed to the speaker -- very, very annoying.

[Re-Titled by Moderator]