Packet loss / super low upload speed

[Thomas__]

Hello, Since more than a week, I can randomly not use internet because of package loss and almost null upload speed as shown in those screenshots from both speed test from google and ping plotter

This makes the connexion properly unusable.
I called your technicians but by speaking english, they told me they will call me back and never called me back.

This issue is on the network side since I : 
Rebooted all related devices (the router, 2 computers and 2 phones)
I reproduced the issue with both phones in WiFi, one laptop in WiFi and Lan, and a desktop on lan (on different port)
I flushed and updated DNS provider
I changed DNS provider (to google providers)
reset completely the router

Technical information: 

Serial Number

2B24GH1L9903078

Firmware version

AR01.04.046.04.14_091322_7244.SIP.20.X2

Hardware Type & Version

9

This is a huge problem for me since I work from home and that the issue can happen at any time.
Can you please contact me back this time ?
Thomas

[Kurtler]

Since August 15th, 2022 there is no more individual support here in the forum. Support in English is available via Facebook or Twitter.

Best regards Kurt