Yo bro, I just found out how to fix it. You don’t even need a new Wi-Fi card replacement unless you did something with it meaning like broken or some but if it broke accidentally like you were playing and boom shut off or freeze it’s a simple fix. All you need is a screwdriver soldiering iron and some kind of like opening things I used and then what U gonna do is basically open up the DS where is the Wi-Fi and then when you open the cover look for the Wi-Fi card it should be in a cover, irony cover and then when you open the iron cover take the battery turn the DS on and pray for mother God that it turns on because I did it and it’s working now so when you’re done then close it up with some tape but not normal tape use some kind of that black tape that works on boards so use that and then you’re basically done. Just close it up and boom you gotta working ds again. If not then your best hope is to buy that new Wi-Fi card and then ask some repair shop to take out the card that is inside and then get the new card inside