Audio only trough headphone

Hi!

I am having trouble how to repair the audio on this device.

(The device has a replaced LCD screen and battery.)

The smartphone was fine until I heard a pop, and then the ear speaker and the loud speaker didn't work, only the headphone with jack.

The device doesn't get stuck in headphone mode, I checked.

Do I need to replace the speaker and/or earphones, or are there any loose wires, or what could be causing the problem?
If I need to replace any parts can I use Nokia 6.2 spare parts, beacause Nokia 7.2 parts are very hard to find.

Thanks in advance for your answers.