Zoho CRM - customfunction - udpaterecords - {"message":"Invalid Ticket Id","code":"4834"}

Zoho CRM - customfunction - udpaterecords - {"message":"Invalid Ticket Id","code":"4834"}

I make a custom function. When I run its code, I have this error:  {"message":"Invalid Ticket Id","code":"4834"}.

This is the code:

ID_Lead=input.idLead.toString();
mapRegNuevo=map();
mapRegNuevo.put("First Name","Nuevo Nombre");
respActualizar = zoho.crm.updateRecord("Leads",ID_Lead,mapRegNuevo);
info respActualizar;

And this is the result:
Executed Successfully
Log messages:
{"message":"Invalid Ticket Id","code":"4834"}

I don't understand why similar code run perfectly in other functions, but doesn't in this case.  :(

I don't find solutions to this matter. 

Please, can you help me?.

Thank you very much in advance