Network connection extremely slow in Ubuntu 20.04 LTS

Please understand the problem before blindly flagging this question as a duplicate

I installed Ubuntu a few months ago and network connection speed was at full bandwidth. However, I have been experiencing very strange network speed drops recently.

Problem Description

Let's say network's bandwith is 20Mb/s. When I first boot up the computer, network is at full bandwidth. After a few minutes of usage, the network speed starts to decrease gradually until it reaches < 0.5Mb/s... Also the decrease is not constant, but the speed keeps spiking and falling back again.

Some weird things I noticed

• The network speed doesn't start decreasing at a fixed moment nor for a fixed period of time.
• If I turn Wifi Off and On, network speed gets better a little bit (not full bandwidth) then it continues to decrease again after a few minutes.

Some assumptions based on the problem description

• My hardware is not damaged because I can dual boot with windows where network speed is perfect
• The issue is most likely caused by a faulty program or misconfiguration (probably with network adapter since the problem doesnt occur with usb connection) because I was not experiencing this issue before on the same machine and on the same ubuntu version.

HOWEVERI could not investigate more in the issue. It seems too vague and weird that I didn't know where to start troubleshooting. Feel free to ask me for any logs.

Some logssudo journalctl -b 0 -u NetworkManager

May 05 21:08:10 LAPTOP-HP NetworkManager[14226]: <warn> [1651781290.6156] sup-iface[0x562aba313a00,wlo1]: connection disconnected (reason -4)
May 05 21:08:10 LAPTOP-HP NetworkManager[14226]: <info> [1651781290.6443] device (wlo1): supplicant interface state: completed -> disconnect>
May 05 21:08:11 LAPTOP-HP NetworkManager[14226]: <info> [1651781291.2362] device (wlo1): supplicant interface state: disconnected -> scanning
May 05 21:08:15 LAPTOP-HP NetworkManager[14226]: <info> [1651781295.7832] device (wlo1): supplicant interface state: scanning -> authenticat>
May 05 21:08:15 LAPTOP-HP NetworkManager[14226]: <info> [1651781295.7976] device (wlo1): supplicant interface state: authenticating -> assoc>
May 05 21:08:15 LAPTOP-HP NetworkManager[14226]: <info> [1651781295.8087] device (wlo1): supplicant interface state: associating -> associat>
May 05 21:08:15 LAPTOP-HP NetworkManager[14226]: <info> [1651781295.8187] device (wlo1): supplicant interface state: associated -> 4-way han>
May 05 21:08:15 LAPTOP-HP NetworkManager[14226]: <info> [1651781295.8714] device (wlo1): supplicant interface state: 4-way handshake -> comp>

These logs are gettings repeated every 1~2 minutes

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