--------> It's just some humanity, therefore it's a must !
Well! ! with all information you gave I would answer : "simply".
Can you provide us with :
The type of connection : ftth, VDSL,ADSL ?
The kind of contract
The Box model you are using, and the way you connect your hosts to it.
Then on degrouptest.com site go to "test d'éligibilité" and give us the results, you'l get NRA (Phone switch name) name, line length and a lot of technical data four your line.
While on this site perform a "Test de débit" and give us the results.
Then, use your box's builtin server at http://Livebox (The admin password of the Livebox is now initialized with the first 8 digits, without any space, of the default WiFi security key.which is printed on the boxes label) and navigate to Support > information system (bad translation) > DSL
Copy paste us the ligne 2.1 to 2.9
Maybe with all that someone here will have some ideas, but befor it's highly not likely.
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