Cause: Laptop uses secondary installed wifi receiver within the WLAN card
Fix:
with your keyboard, press windows icon + R
type "devmgmt.msc" without quotes, press enter or click OK
on the device manager, double click or expand Network Adapters, double click wifi driver/adapter, example broadcom adapter
at the top menu, click Advanced
On Property list: click "Antenna Diversity"
Value in default is Aux, set it to Main
click OK
babalik ang wifi signal strength ng laptop