Swift_TransportException Expected response code 250 but got code "530", with message "530 5.7.1 Authentication required "

I am new to Laravel and looking to enhance my skills in using Laravel framework 5.4. But I don't know what to do when I encounter this error: 1/1) Swift_TransportException Expected response code 250 but got code "530", with message "530 5.7.1 Authentication required Is it .

via Chebli Mohamed