management accounts

function sendSlackMessage(e) {
  var app = SpreadsheetApp;
  var ss = app.getActiveSpreadsheet();
  var activeSheet =ss.getActiveSheet();
  //activeSheet.getRange().setValue();
    status = e.value;
    range = e.range;
  
  if (e.range.getColumn() === 12) {
    let source = e.source;
    let row = e.range.getRow();
    let Project = source.getActiveSheet().getRange (row, 3, 1, 1,).getValue();
    let ProjectCode = source.getActiveSheet().getRange (row, 4, 1, 1,).getValue();
    let DatePaid = e.value;
    let url ="https://hooks.slack.com/services/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";
    
    let payload = {
    text: "🎉🎆🎉*We received payment* from "+ Project + " on "+ DatePaid + " PM's please get the " + ProjectCode+ " team to send their *Consultant invoices* to accounts for the Payment Calculation that is due as per the Economics Sheet. 🎊"
    }
  
    let headers = {
    'Content-type': 'application/json'
    }
    let options = {
    headers: headers,
    method:'POST',
    payload:JSON.stringify(payload)
    }
    UrlFetchApp.fetch(url, options);
  }else {
    console.log("DatePaid was not updated,the column was:",e.range.getcolumn())
  }
 
}