If everything else is good about the laptop for you.
I'd just buy another NIC, such as Intel AX210 Wireless AX210NGW which I have put in both of the laptop I own, and they work flawlessly. They originally had Realtek NIC's which worked fine but I wanted more and this one from Intel is gold ~imo.
Honestly, NIC's, have been hit n miss across the whole range of manufacturers inc Intel with duds. It's 60 dollars AUD to fix with something that works. Just a thought. I mean completely up to you how you go about solving the issue and understand that something shinny and new should just work perfectly.
If the shop does it takes about 10 minutes - 15 minutes, if you include a coffee.
We have strong consumer laws, but this should not effect your warranty whatsoever.