nevermind i got it :]

the output is #

What does your solution return for following test case? What should it return?

generateHashtag(" ".repeat(200))

You are getting the same error all the time because you have the same bug all the time.

We do not know what bug it is, because we do not know your code.

can anyone please tell me why do i keep getting this same error?the error, Still an empty string: expected '#' to equal false

This seems to be a very poorly written test. A lot of the conditions are only made clear in the test cases, and the description explicitly states that the method should return false in some cases and String in others, yet the method return value is String. It's not clear that it actually means it should return an empty string when it's invalid, unless you look at the tests