Error when checking between starts_on and ends_on in Event Doc

Hi,
With the below code I am getting a whole heap of events listed that are not between the range specified on the event form starts_on and ends_on code

frappe.call({
“method”:“frappe.client.get_list”,
args: {
doctype:“Event”,
filters: { “docstatus”:["!=",2], “ends_on”:[“between”,[frm.doc.starts_on,frm.doc.ends_on]]},
fields: [“name”,“starts_on”,“ends_on”]
},
async:false,
callback: function(eventcheck) {
… etc
returns many events which are not in the specified range,