一个特定网络不适用于我的 Ubuntu 20.02 笔记本电脑。这是我的主要家庭 wifi 网络。另一方面，我可以连接到其他家庭 Wifi 网络（但后者网络的信号很差）。
无法使用的 wifi 连接名为“Ziggo-ap-4a3dc0b”。这个 wifi 连接在我的 Android 智能手机和 Windows 台式电脑上完美运行，但在笔记本电脑上却不行。我无法用笔记本电脑连接到“Ziggo-ap-4a3dc0b”。
问题现已解决。路由器出现问题。路由器的设置现在正确，并且 wifi 连接正常。
然后我iwlist wlp2s0 scanning在终端中使用。输出报告如下。我报告了不起作用的网络“Ziggo-ap-4a3dc0b”的输出，并报告了起作用的网络“Ziggo0382799”的输出：
Cell 01 - Address: 18:35:D1:35:21:C7
Channel:36
Frequency:5.18 GHz (Channel 36)
Quality=30/70 Signal level=-80 dBm
Encryption key:on
ESSID:"Ziggo0382799"
Bit Rates:6 Mb/s; 9 Mb/s; 12 Mb/s; 18 Mb/s; 24 Mb/s
36 Mb/s; 48 Mb/s; 54 Mb/s
Mode:Master
Extra:tsf=000001b33089f25a
Extra: Last beacon: 4196ms ago
IE: Unknown: 000C5A6967676F30333832373939
IE: Unknown: 01088C129824B048606C
IE: Unknown: 030124
IE: Unknown: 073C4555202401172801172C01173001173401173801173C011740011764011E68011E6C011E70011E74011E78011E7C011E80011E84011E88011E8C011E
IE: Unknown: 460573D000000C
IE: Unknown: 2D1AEF091BFFFFFF0000000000000000000100000000000000000000
IE: Unknown: 3D1624050400000000000000000000000000000000000000
IE: Unknown: 4A0E14000A002C01C800140005001900
IE: Unknown: 7F0805000F0200000040
IE: Unknown: BF0CB2018033EAFF0000EAFF0000
IE: Unknown: C005012A00FCFF
IE: Unknown: C30402D2D2D2
IE: Unknown: DD180050F2020101840003A4000027A4000042435E0062322F00
IE: Unknown: DD0900037F01010000FF7F
IE: IEEE 802.11i/WPA2 Version 1
Group Cipher : CCMP
Pairwise Ciphers (1) : CCMP
Authentication Suites (1) : PSK
IE: Unknown: DD9F0050F204104A0001101044000102103B00010310470010098F6F4876815770B0A001E3963000DD1021001C41746865726F7320436F6D6D756E69636174696F6E732C20496E632E102300044150787810240008415078782D7878781042001253657269616C204E756D62657220486572651054000800060050F20400011011000941746865726F734150100800020104103C0001021049000600372A000120```
```Cell 02 - Address: 34:E8:94:A3:DC:0B
Channel:6
Frequency:2.437 GHz (Channel 6)
Quality=57/70 Signal level=-53 dBm
Encryption key:on
ESSID:"Ziggo-ap-4a3dc0b"
Bit Rates:11 Mb/s; 12 Mb/s; 18 Mb/s; 24 Mb/s; 36 Mb/s
48 Mb/s; 54 Mb/s
Mode:Master
Extra:tsf=000000001ced8ea1
Extra: Last beacon: 10072ms ago
IE: Unknown: 00105A6967676F2D61702D34613364633062
IE: Unknown: 01079618243048606C
IE: Unknown: 030106
IE: Unknown: 07064E4C20010D14
IE: Unknown: 2A0100
IE: Unknown: 2D1AAD011BFFFFFF0000000000000000000100000000000000000000
IE: Unknown: 3D1606080000000000000000000000000000000000000000
IE: Unknown: 7F080000000000000040
IE: Unknown: DD180050F2020101800003A4000027A4000042435E0062322F00
IE: Unknown: DD0900037F01010000FF7F
IE: Unknown: DD9F0050F204104A00011010440001021057000101103B00010310470010123456789ABCDEF0123434E894A3DC0B1021000754502D4C494E4B10230018457874726120776966692D70756E74205A6967676F20433710240003322E3010420003312E301054000800060050F204000110110019576972656C65737320526F7574657220417263686572204337100800022008103C0001031049000600372A000120
IE: IEEE 802.11i/WPA2 Version 1
Group Cipher : CCMP
Pairwise Ciphers (1) : CCMP
Authentication Suites (1) : PSK```
Then I used ```tail -f /var/log/syslog```, and the output is:
```Dec 31 20:34:01 nico-Nitro-AN515-51 kernel: [ 656.978153] wlp2s0: Limiting TX power to 23 (23 - 0) dBm as advertised by c6:c9:e3:27:55:c3```
```Dec 31 20:34:01 nico-Nitro-AN515-51 wpa_supplicant[867]: wlp2s0: CTRL-EVENT-SIGNAL-CHANGE above=0 signal=-86 noise=-100 txrate=6000```
I also used ```sudo journalctl -b 0 -u NetworkManager```. These warnings were shown in the terminal:
```NetworkManager[825]: <warn> [1609442589.4993] ifupdown: interfaces file /etc/network/interfaces doesn't exist```
```<warn> [1609442589.9571] Error: failed to open /run/network/ifstate```
```<warn> [1609442590.0718] sup-iface: failed to cancel p2p connect: P2P cancel failed.```
**What can I do to make my main home Wifi network work?**