According to Support, If you get the message stating that your username or password is incorrect when you connect to the game from the Ankama Launcher, even though these are correct, this could be because the IP address of your Wifi or 3G/4G connection changes between connecting to the Launcher and launching the game.
Have you tried a different connection?
See message in context
Have you tried a different connection?
Have you tried a different connection?
I'm very sorry to hear that.
I invite you to write a ticket to the Support team so they can look into it and help you out.
In the future, I suggest you open a new topic on your issue in order to receive some assistance if you cannot find a solution! Not only is it easier for us to track your issue this way, but it prevents reviving some old forum topics.
Thank you for your understanding!