Realme
Turn On/Off Auto-Switch to Receiver auf Realme
On phones running Realme UI, a call started on speaker mode normally stays on speaker until you tap the icon again. The Auto-switch to receiver feature uses the proximity sensor to detect when you lift the phone to your ear and moves the audio back to the earpiece without any manual tap.
The toggle sits inside the convenience tools section rather than the general call settings, which is why many people never find it.
Menu path
Open Settings ➔ Convenience tools ➔ Gestures & motions ➔ toggle Auto switch to receiver.
Turn it on to let the earpiece take over automatically once you lift the phone. Turn it off if you want speaker mode to stay active no matter how you hold the phone, for example while using a car mount or a thick case.
If the switch does not happen after enabling the option, check whether a case, skin, or screen protector covers the proximity sensor near the earpiece. Dust or a smudge on that spot can also delay or block detection.