Gfilui

I updated from Ubuntu 14.04 to 16.04 LTS and my wifi stopped working. I followed this post and found that my Network Manager was not running so I manually started my network manager by using the command sudo service network-manager start this started the Network Manager, but when I try to connect with the desired Network it fails after trying for a while. Below are some of the diagnostics received following the post mentioned above.

##### lspci #############################

04:00.0 Network controller [0280]: Qualcomm Atheros AR928X Wireless Network Adapter (PCI-Express) [168c:002a] (rev 01)
 Subsystem: Foxconn International, Inc. T77H047.31 802.11bgn Wireless Half-size Mini PCIe Card [AR9283] [105b:e01f]
 Kernel driver in use: ath9k

##### rfkill ############################

1: phy0: Wireless LAN
 Soft blocked: no
 Hard blocked: no

##### lsmod #############################

acer_wmi 20480 0
sparse_keymap 16384 1 acer_wmi
ath9k 143360 0
ath9k_common 36864 1 ath9k
ath9k_hw 466944 2 ath9k_common,ath9k
ath 32768 3 ath9k_common,ath9k,ath9k_hw
mac80211 737280 1 ath9k
cfg80211 565248 4 ath,ath9k_common,ath9k,mac80211
wmi 20480 1 acer_wmi
video 40960 2 i915,acer_wmi

##### interfaces ########################

[/etc/network/interfaces]
auto lo
iface lo inet loopback

##### ifconfig ##########################

wlan0 Link encap:Ethernet HWaddr <MAC 'wlan0' [IF2]> 
 UP BROADCAST MULTICAST MTU:1500 Metric:1
 RX packets:28 errors:0 dropped:20 overruns:0 frame:0
 TX packets:24 errors:0 dropped:0 overruns:0 carrier:0
 collisions:0 txqueuelen:1000 
 RX bytes:2349 (2.3 KB) TX bytes:4031 (4.0 KB)

##### iwconfig ##########################

wlan0 IEEE 802.11bgn ESSID:off/any 
 Mode:Managed Access Point: Not-Associated Tx-Power=15 dBm 
 Retry short limit:7 RTS thr:off Fragment thr:off
 Power Management:off

##### network managers ##################

Installed:

 NetworkManager

Running:

root 2123 1 0 06:58 ? 00:00:00 /usr/sbin/NetworkManager --no-daemon

##### NetworkManager info ###############

GENERAL.DEVICE: wlan0
GENERAL.TYPE: wifi
GENERAL.NM-TYPE: NMDeviceWifi
GENERAL.VENDOR: Qualcomm Atheros
GENERAL.PRODUCT: AR928X Wireless Network Adapter (PCI-Express) (T77H047.31 802.11bgn Wireless Half-size Mini PCIe Card [AR9283])
GENERAL.DRIVER: ath9k
GENERAL.DRIVER-VERSION: 4.4.0-72-generic
GENERAL.FIRMWARE-VERSION: N/A
GENERAL.HWADDR: <MAC 'wlan0' [IF2]>
GENERAL.MTU: 0
GENERAL.STATE: 30 (disconnected)
GENERAL.REASON: 0 (No reason given)
GENERAL.UDI: /sys/devices/pci0000:00/0000:00:1c.1/0000:04:00.0/net/wlan0
GENERAL.IP-IFACE: 
GENERAL.IS-SOFTWARE: no
GENERAL.NM-MANAGED: yes
GENERAL.AUTOCONNECT: yes
GENERAL.FIRMWARE-MISSING: no
GENERAL.NM-PLUGIN-MISSING: no
GENERAL.PHYS-PORT-ID: --
GENERAL.CONNECTION: --
GENERAL.CON-UUID: --
GENERAL.CON-PATH: --
GENERAL.METERED: unknown
CAPABILITIES.CARRIER-DETECT: no
CAPABILITIES.SPEED: unknown
CAPABILITIES.IS-SOFTWARE: no
WIFI-PROPERTIES.WEP: yes
WIFI-PROPERTIES.WPA: yes
WIFI-PROPERTIES.WPA2: yes
WIFI-PROPERTIES.TKIP: yes
WIFI-PROPERTIES.CCMP: yes
WIFI-PROPERTIES.AP: yes
WIFI-PROPERTIES.ADHOC: yes
WIFI-PROPERTIES.2GHZ: yes
WIFI-PROPERTIES.5GHZ: no
CONNECTIONS.AVAILABLE-CONNECTION-PATHS: /org/freedesktop/NetworkManager/Settings/5,6,1
CONNECTIONS.AVAILABLE-CONNECTIONS[1]: 71b17be3-048d-443b-9d50-b8090716ee03 | tahir banuri
CONNECTIONS.AVAILABLE-CONNECTIONS[2]: d471c531-2d64-4160-8104-e1be06d3c15e | PTCL-GPON
CONNECTIONS.AVAILABLE-CONNECTIONS[3]: 76714b7c-1ae2-467d-a173-d7136757627b | tahir banuri 1

SSID BSSID MODE CHAN FREQ RATE SIGNAL BARS SECURITY ACTIVE * 
PTCL-GPON <MAC 'PTCL-GPON' [AC2]> Infra 1 2412 MHz 54 Mbit/s 60 ▂▄▆_ WPA1 no 

##### NetworkManager.state ##############

[main]
NetworkingEnabled=true
WirelessEnabled=true
WWANEnabled=true
WimaxEnabled=true

##### NetworkManager profiles ###########

[[/etc/NetworkManager/system-connections/PTCL-GPON]] (600 root)
[connection] id=PTCL-GPON | type=wifi | permissions=
[wifi] mac-address=<MAC 'wlan0' [IF2]> | mac-address-blacklist= | ssid=PTCL-GPON
[ipv4] method=auto
[ipv6] method=auto

##### iwlist channels ###################

wlan0 13 channels in total; available frequencies :
 Channel 01 : 2.412 GHz
 Channel 02 : 2.417 GHz
 Channel 03 : 2.422 GHz
 Channel 04 : 2.427 GHz
 Channel 05 : 2.432 GHz
 Channel 06 : 2.437 GHz
 Channel 07 : 2.442 GHz
 Channel 08 : 2.447 GHz
 Channel 09 : 2.452 GHz
 Channel 10 : 2.457 GHz
 Channel 11 : 2.462 GHz
 Channel 12 : 2.467 GHz
 Channel 13 : 2.472 GHz

##### iwlist scan #######################

Channel occupancy:

 3 APs on Frequency:2.412 GHz (Channel 1)
 1 APs on Frequency:2.452 GHz (Channel 9)

wlan0 Scan completed :

 Cell 02 - Address: <MAC 'PTCL-GPON' [AC2]>
 Channel:1
 Frequency:2.412 GHz (Channel 1)
 Quality=48/70 Signal level=-62 dBm 
 Encryption key:on
 ESSID:"PTCL-GPON"
 Bit Rates:1 Mb/s; 2 Mb/s; 5.5 Mb/s; 11 Mb/s; 6 Mb/s
 9 Mb/s; 12 Mb/s; 18 Mb/s
 Bit Rates:24 Mb/s; 36 Mb/s; 48 Mb/s; 54 Mb/s
 Mode:Master
 Extra:tsf=0000008f52de4a5d
 Extra: Last beacon: 4ms ago
 IE: WPA Version 1
 Group Cipher : CCMP
 Pairwise Ciphers (1) : CCMP
 Authentication Suites (1) : PSK

##### module infos ######################

[ath9k]
filename: /lib/modules/4.4.0-72-generic/kernel/drivers/net/wireless/ath/ath9k/ath9k.ko
license: Dual BSD/GPL
description: Support for Atheros 802.11n wireless LAN cards.
author: Atheros Communications
srcversion: 591F25EEE2294D51A1DE1FE
depends: mac80211,ath9k_hw,ath9k_common,cfg80211,ath
intree: Y
vermagic: 4.4.0-72-generic SMP mod_unload modversions 
parm: debug:Debugging mask (uint)
parm: nohwcrypt:Disable hardware encryption (int)
parm: blink:Enable LED blink on activity (int)
parm: led_active_high:Invert LED polarity (int)
parm: btcoex_enable:Enable wifi-BT coexistence (int)
parm: bt_ant_diversity:Enable WLAN/BT RX antenna diversity (int)
parm: ps_enable:Enable WLAN PowerSave (int)
parm: use_chanctx:Enable channel context for concurrency (int)

[ath9k_common]
filename: /lib/modules/4.4.0-72-generic/kernel/drivers/net/wireless/ath/ath9k/ath9k_common.ko
license: Dual BSD/GPL
description: Shared library for Atheros wireless 802.11n LAN cards.
author: Atheros Communications
srcversion: 6FBD9F8A613FDFA282AB4FE
depends: ath9k_hw,cfg80211,ath
intree: Y
vermagic: 4.4.0-72-generic SMP mod_unload modversions 

[ath9k_hw]
filename: /lib/modules/4.4.0-72-generic/kernel/drivers/net/wireless/ath/ath9k/ath9k_hw.ko
license: Dual BSD/GPL
description: Support for Atheros 802.11n wireless LAN cards.
author: Atheros Communications
srcversion: FA7ECFBA5761A5B3ED96BB2
depends: ath
intree: Y
vermagic: 4.4.0-72-generic SMP mod_unload modversions 

[ath]
filename: /lib/modules/4.4.0-72-generic/kernel/drivers/net/wireless/ath/ath.ko
license: Dual BSD/GPL
description: Shared library for Atheros wireless LAN cards.
author: Atheros Communications
srcversion: 3FCDBF7CE71CB8FB980D59D
depends: cfg80211
intree: Y
vermagic: 4.4.0-72-generic SMP mod_unload modversions 

[mac80211]
filename: /lib/modules/4.4.0-72-generic/kernel/net/mac80211/mac80211.ko
license: GPL
description: IEEE 802.11 subsystem
srcversion: 95AEC776A5F508489477F0E
depends: cfg80211
intree: Y
vermagic: 4.4.0-72-generic SMP mod_unload modversions 
parm: minstrel_vht_only:Use only VHT rates when VHT is supported by sta. (bool)
parm: max_nullfunc_tries:Maximum nullfunc tx tries before disconnecting (reason 4). (int)
parm: max_probe_tries:Maximum probe tries before disconnecting (reason 4). (int)
parm: beacon_loss_count:Number of beacon intervals before we decide beacon was lost. (int)
parm: probe_wait_ms:Maximum time(ms) to wait for probe response before disconnecting (reason 4). (int)
parm: ieee80211_default_rc_algo:Default rate control algorithm for mac80211 to use (charp)

[cfg80211]
filename: /lib/modules/4.4.0-72-generic/kernel/net/wireless/cfg80211.ko
description: wireless configuration support
license: GPL
author: Johannes Berg
srcversion: A7DC879B6551813C20004F1
depends: 
intree: Y
vermagic: 4.4.0-72-generic SMP mod_unload modversions 
parm: bss_entries_limit:limit to number of scan BSS entries (per wiphy, default 1000) (int)
parm: ieee80211_regdom:IEEE 802.11 regulatory domain code (charp)
parm: cfg80211_disable_40mhz_24ghz:Disable 40MHz support in the 2.4GHz band (bool)

Thank you.