401 error connecting to the websocket with livekit

Hi to everyone,

we are experiencing a 401 error related to the connection of the websocket (in reference to our web app); we are unable to start the video call.
We only encounter this problem when connected users from France try to start the video call. We tried to replicate the problem, using the same devices, the same time zone and language settings of the system and browser and activating a vpn that would register us in France; but we couldn’t replicate it.
We asked our users to change their wifi, switch browser,
to use the incognito tab, have the cache cleared, use the hotspot and update operating systems but the error always occurs.
Our users in Italy and England have no problem.
Our french users have been experiencing the problem since we brought the version containing livekit to pre prod. If they use an old version that doesn’t have Livekit they don’t experience the problem.
We have installed a chrome plugin that takes care of testing websockets,
The link on our browser works and logically we would have expected the same operation performed on their browser to fail therefore we asked them to install the plugin and try. This operation gave a positive result, so the same operation performed by a call under our domain and in a normal browser tab gives different results.
Does anyone have an idea what could be causing this problem?
Could be a Livekit connectivity problem with the french network, has anyone had such an experience?
Any advice will be welcome, thanks