diff --git a/index.js b/index.js
index f5ceb83..2e63597 100644
--- a/index.js
+++ b/index.js
@@ -102,13 +102,18 @@ function updateRecords(data, root) {
 	return data;
 }
 
+function getStartOfDayTimestamp(date) {
+    const startOfDay = new Date(date.getFullYear(), date.getMonth(), date.getDate());
+    return startOfDay.getTime(); // Returns the timestamp in milliseconds
+}
+
 async function sendSummary() {
 	const data = await getPreviousDayData();
 	const root = await loadRecords();
 	const updatedData = await updateRecords(data, root);
 	await saveRecords(root);
 
-	const previousDayStart = new Date(Date.now() - 86400000);
+	const previousDayStart = new Date(getStartOfDayTimestamp(new Date()));
 	const previousDayEnd = new Date(previousDayStart);
 	previousDayEnd.setHours(23, 59, 59, 999);