merge queries

Hello

we have a process to check between 2 data sources on monthly basis to track users, I have created a merged query where the first file is the main file and the second is emp data with all user data

I've used left join with main file as left 

I'm getting data in both the columns even when emp data doesnot contain that record but main file consists it 

present result

 date  main file  emp data

jan'23    aaa       aaa

feb'23   aaa       aaa

mar'23  aaa      aaa

 expected result

 date  main file  emp data

jan'23    aaa       aaa

feb'23   aaa       aaa

mar'23  aaa      null