Unfortunately the given USer/Password is not working. Would you please kindly double check the information given?
Alsi, would you please kindly change the theme of the website from the Child Theme to Parent theme and see if it fixes the issue? If yes you will need to go to your Themeco Dashboard and download the correct Child Theme:
You need to backup your website completely and delete the Child Theme and install the new one:
Then you need to move your customization to the new Child Theme.