Every time I enter the launcher I am said that my password is not correct

Every time I enter my launcher, no matter if the "keep me logged in" button is on, I am asked to put my email and password. The thing is that when I write them, the "Password is incorrect" sign comes out. 

I then try to change my password and the "you can not use the same password" sign comes out.

I double checked if I was spelling something wrong but that is not the case.

Please help me. I am running out of password ideas