Paste special values using a script

I am a beginner and need to write a simple script to paste special values in Google Sheets. I tried the below script, but it's not working.

function livedata_Function() {    var spreadsheet = SpreadsheetApp.getActiveSpreadsheet().getSheetByName("Live_Data");    spreadsheet.getRange('L3:T1378').copyTo(spreadsheet.getRange("K3"), SpreadsheetApp.CopyPasteType.PASTE_VALUES, false);}