Vostro 5590 model changed by kid

Son (lil kid) of my friend was somehow able to change the model of a DELL notebook.

He pressed random keys during POST. He saw a question about what model is it and picked randomly. That's a mother story.

It show now DELL 5490 in the BIOS and this model does not have a onboard LAN.

Because of that LAN in this notebook isn't working anymore.

We need to change that model to 5590 but factory reset in BIOS didn't do a job.

Can you help me? Google provided me no useful information.