First make sure your wireless is On
And try that with connect another wifi like you phone " Hotspot "
If the connection is successful that is fine , and there is no problem from your laptop
Then try to connect to the Modem from another laptop or phone , to make sure everything is ok
In your laptop, go to the name of the wireless, and forget it " remove the password " and try to connect again
Try with trapshooting ..
- Maybe the channel of your modem , sometimes be the reason
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