WiFi asks for password again and again

The Problem

• My WiFi network disconnects itself randomly and starts asking for password.
• The password is already stored, I just have to click on connect.
• When I click on connect, it remains connected for some time then again disconnects and sometimes it even does not connects.
• The speed while being connected is very low and torrents are not downloading.
• When I sometimes connect to WiFi I get System encountered a error dialogue box

What did I do

• I go to Edit connections and make sure that All users can connect is ticked.
• I also deleted config file of connection from /etc/NetworkManager/system-conncections

I still can't connect to WiFi sometimes and it disconnects automatically if I'm ablee to get connected after some time. So what should I do?

After googling I found that this problem has been encountered in earlier versions, I'm using Ubuntu 16.04 so if there is a permanent solution which can help everyone that will be the best.

P.S.- I have already tried these links:

• My wireless/WiFi connection does not work. What information is needed to diagnose the issue?
• WiFi repeatedly asks for password (Ubuntu 12.10 fresh)
• http://www.askubuntu.com/questions/285287/wifi-keeps-asking-for-password-ubuntu-12-10 .

Also the WiFi network works fine with my mobile.If more information is needed than let me know and how I can find it.

Also after seeing this I have a hardware detection problem, what logs do I need to look into? i found that no card was soft or hard blocked and rest info I found after using commands are on http://paste.ubuntu.com/19615988/

Output of lspci -knn | grep Net -A2

02:00.0 Network controller [0280]: Intel Corporation CentrinoWireless-N 130 [8086:0896] (rev 34)
Subsystem: Intel CorporationCentrino Wireless-N 130 BGN [8086:5005] Kernel driver in use: iwlwifi

New Update: I can't connect to my WiFi network, I have to use USB tethering in mobile to use internet on my laptop.