SQL to Get Grade and Grade and Grade Step details on a assignment

Summary:

Hello Everyone,

I'm new to SQL query building. Just getting hands on it. I am trying to create a Data model that will return salary detail including Grade and Grade step in the given Data range. I have written a SQL query and its returning the Data. However, the issue is, it returning duplicate records. Like

in the screenshot.

Something is wrong with the Joins I have used in my Query. Can you please help here.

Thanks in advance!

Content (required):

Version (include the version you are using, if applicable):

Code Snippet (add any code snippets that support your topic, if applicable):