Why is the apple genius bar charging me for a service fee?

As a guess, this might be an AppleCare+ service fee for broken front and rear glass.

As for what the fee might actually involve, you’ll have to ask Apple.

AI-generated text is glorified autocorrect. Not a particularly reliable reference

• So, where are you seeing this Service Fee?
• What work was done on the device?

You need to ask Apple but they do not respond here.