Is my wifi adapter affected?

Hello,

I had my laptop repaired for a keyboard issue. Now my keyboard issue is fixed but when I brought my laptop back home a strange thing with the network connection is occurring. my router is okay and all of the other devices at home are getting good connection status from anywhere around the house. But not my laptop. though my other devices are recognising few other signal from outside, my laptop is only showing my own router signal (and strangely enough, same signal twice). anyway, when I bring the laptop close to router, it seems to connect without a problem. when I take my laptop away(in another room) the connection seems to have disconnected or show network error. I have tried all possible troubleshooting I could think of, like- updating network adapter, rolling back network adapter, restarting PC and router, checking driver status etc. nothing seemed to work at all. what could be the cause of problem here? also should I charge the IT shop people whom I gave the laptop to fix my keyboard? because I didn't have any problem on this matter before their repairing.