I am able to create Event record using Custom Function with this Map

{"SEMODULE":"Leads","Start_DateTime":"2018-06-29T08:00:00-05:00","SEID":1259849000008435235,"SMOWNERID":" jared@xxxxx.com","Event_Title":"Date held for John Doe Wedding","End_DateTime":"2018-06-29T15:00:00-05:00"}

But the lead record is not linking. Why?