Just solved it.   The problem is with the latest Radeon driver. Just install the official driver from Dell and it will bring back the sound.  
As said, the problem is with the system audio which is the built in speakers of the laptop , It just randomly stopped working but I can still use the audio and microphone if I connect any blue tooth device but without it, there is no audio coming at all. I've had the device for a little over a year and this is the first time I've faced this issue. I've tried updating the drivers and re-installing but it still wouldn't work. The most recent windows update I had was KB5019959 and KB5020687. Any assistance on this? 
Dell G15 5515 Ryzen 5 5600h - System Audio problem