Hi @Straff Do you have Hdmi control switched on? Go to settings,General,External Device Manager and check Anynet Plus(HDMI-CEC) .
If still issues check you have the latest Tv firmware. possibly may need to disconnect devices,switch off for a minute and reconnect. A Factory Reset is another option though not first choice.
I do not work for Samsung or make Samsung Products but provide independent advice and valuable contributions.
My Device- S21 Ultra 5G ( SM-998B/DS ) CSC= BTU , 12GB/256GB
One Ui 5.0,Android 13 .