As a process of elimination can you try your sim card in another phone @Jigz ?
Does this happen in one place or everywhere ?
Also it maybe beneficial to check in with your Network Provider.
Current Phone ~
Samsung Note 20 Ultra 5G SM-N9860_256Gb SnapDragon 865+
Samsung One Ui 3.1/ Android 11.
I also have had the same issue with the recent update. I have no idea if I have managed to call someone or its failed to connect until I hear someone say hello the other end. Anyone found a solution?
That's a strange one. Is the issue occurring with contacts saved to the device, or when you manually dial a number? Can you try pressing the Volume Down and Power buttons together for around 10 seconds until the phone restarts, as this will refresh the device and address any issues that may be affecting the Phone app. In the meantime, as a possible workaround, open the Phone app > Tap the 3 dots in the top right > Settings > Call Alerts and Ringtones > Play Tone When Call Connects > On.