Multi conditions if clauses does not work properly

Question

I want to add a new column in a df according to values in two columns. My code is like this but all conditions are not met when run my code:

def Modify_location_df(df):

    if (df['Family'] != 'Roof') and (df['Reference Level Elevation'] == '0'):
    
       return 'First Floor'
    elif (df['Family'] != 'Roof') and (df['Reference Level Elevation'] == '335'):
    
       return 'Attic floor'
    else:
       return 'Pitched Roof'


 df['Location'] = df.apply(Modify_location_df, axis = 1)

My Data frame before applying the code

My Data frame after applying the code (the first row should be 'Pitched roof' but it's not)