Ce probmème peut être dû à une surcharge des serveurs en cette période d'enseignement à distance généralisé, mais il s'agit plus certainement d'un problème de comptes et de droits d'accès.

💡 If you are not already using the most recent version of Google Chrome as you browser, it would be good to switch to it. You can download it here if you don’t already have it: https://www.google.com/chrome/browser/desktop/index.html
💡 It’s also a good idea to make sure you’re not logged into any other Gmail accounts (like a personal Gmail account) at the same time.
💡You could also try clearing your browser’s cache as described in this article (French version here).
Then please do the following:
- Log out of your Google account.
- Completely close the browser.
- Re-launch the browser.
- Log back into your Google account.
💡You might also try using an Incognito window to see if you get a different outcome. In Chrome, click on the menu bar in the upper right corner of the browser (three horizontal lines). Then choose "New incognito window".