Wifi and Bluetooth signal very weak

My laptop got repaired 2 days ago and since then both wifi and Bluetooth are showing really weak strength , so weak that if the router is within 1 meter only then internet would work, if I go 3-4 meters away from the router it will remain connected but internet would not work.Same problem with the bluetooth, I have to keep my wireless earphone onto the laptop only then sound will come out of earphone, at merely 3 meters away Bluetooth gets disconnected.What is the problem and how to get it fixed?Did the mechanic loose some wires unintentionally?