[PDOException]- SQLSTATE[HY000] [1045] Access denied for user 'root'@'ip' (using password: YES)

I am trying to connect to AWS through ssh in order to migrate some files. I connected successfully using the following command:

ssh -i ~/Downloads/key.pem ec2-user@myuser

Then, I tried to run the following :

php artisan migrate

I got the following:

[PDOException]                                                               
  SQLSTATE[HY000] [1045] Access denied for user 'user'@'ip' (using password: YES)

What could be preventing me from accessing my DB in order to migrate?!