I can't logout

Hello, I wanted to inform you that I cannot connect to my Mojang account with the launcher. I paid well for the game "Minecraft" but when I connect with the launcher to be able to play they tell me "Invalid email address or password" I don't know why they tell me that when I have returned the correct password and the correct email. I have already changed my password several times but nothing has changed. Thank you for answering me as soon as possible.