Code failed to give output

I am working on my project (Clean And Analyze Employee Exit Surveys). I tried running the code below but I couldnt get the out put displayed. What could be the problem??

Check the unique values


Out[20]: Below is the output

Series(, Name: cease_date, dtype: int64)

Hi @wolewani:

Please attach the mission link as per these guidelines so we know the particular mission you are referring to and format your code too so that we can better assist. Thanks!