I"m stack with user story 12 in creating my technical documentation page , help plz!

here are my codes

read more than the first line when you look at a failing test, for example, the error message of the first failing tests say:

Check that these headers have corresponding .nav-link elements and be mindful of case! : WHAT YOU SHOULD ALREADY KNOW,WHILE STATEMENT : expected 2 to equal 0
AssertionError: Check that these headers have corresponding .nav-link elements and be mindful of case! : WHAT YOU SHOULD ALREADY KNOW,WHILE STATEMENT : expected 2 to equal 0

thanks,that was helpful
i should be careful next time