Getting Authentication error during execution of custom function

Getting Authentication error during execution of custom function

I am trying to write below custom function for automated workflow in my developer edition for trial version which triggers it
(Removed create Record logic below)

leadDetails = zoho.crm.getRecords("Leads");
info leadDetails;

I tried to execute it for test. It throws authentication error.
{"code":"AUTHENTICATION_FAILURE","details":{},"message":"Authentication failed","status":"error"}

It works fine if I use it in trial version.
Is the command different for developer? I will appreciate the help.