Hi Ali,
I'm going to agree with daniel (@tech_ni). The camera flex tends to be glued down really well and the stress of disengaging the adhesive can easily break the delicate connections between the two flex cables that are soldered together to make up the front camera assembly.
I have replaced two of them on iPhone 7 Pluses for about $5 USD each, so it's not an expensive part. The first time was because my wife's phone started boot looping and that fixed it, the second time was when I broke the connector doing a screen replacement.
An easy and cheap fix, definitely not time to start messing with motherboard repairs yet.