custom properties

In a deal module under the sales module I want to get all the custom fields through the API ,I am unable to get the custom poprerty in API responce ,I want the property key name to pass in the property

Last Deal Stage , Closed Lost Reason , Closed Won Reson want this property key name

Hi, @mapplecode2020 :waving_hand: Can you provide an example of your request URL? As well as the specific endpoint you are using?

Thank you! — Jaycee