New Words couldn't loading

Hi @galipdemirtas, as the the pop-up mentions, this is caused by Grammar.
Grammar levels are displayed on our website, but they can only be accessed by logging in on your iOS or Android mobile apps. Due to the inconsistencies in the number of items, this causes Learn New Words to display an error. Please note that you may have completed this course (you can check this by clicking on the course’s title and ensuring that all the levels have a flower icon), so in the meanwhile, you will just need to ignore the Grammar levels to fix this (simply click on a Grammar level on web and then select ‘Ignore this level’):

How to ignore items and levels