main, fix rescheduling by making each day's alarm ID unique so that it does not cancel the alarm currently going off.

lib/main.dart

@@ -88,7 +88,12 @@ class _HomeScreenState extends State<HomeScreen> {
   String? _minuteErrorText;
   bool _validTime = false;
 
-  static const _alarmId = 1001;
+  static int _alarmId = 20260000;
+
+  int dateAsId(DateTime d) => d.year * 10000 + d.month * 100 + d.day;
+  int todayAsId() {
+    return dateAsId(DateTime.now());
+  }
 
   @override
   void initState() {
@@ -99,7 +104,10 @@ class _HomeScreenState extends State<HomeScreen> {
     // Reschedule alarm any time one goes off.
     Alarm.ringing.listen((AlarmSet alarmSet) {
       for (final alarm in alarmSet.alarms) {
-        if (alarm.id == _alarmId) _scheduleAlarm();
+        if (alarm.id == todayAsId()) {
+          _scheduleAlarm();
+          break;
+        }
       }
     });
   }
@@ -249,7 +257,9 @@ class _HomeScreenState extends State<HomeScreen> {
       alarmTime = alarmTime.add(const Duration(days: 1));
     }
 
-    _debug("_scheduleAlarm, alarmTime=" + alarmTime.toIso8601String());
+    _debug("_scheduleAlarm, alarmTime=${alarmTime.toIso8601String()}");
+    _alarmId = dateAsId(alarmTime);
+    _debug("_alarmId=$_alarmId");
 
     if (Platform.isLinux) {
       // Linux: use a Timer (app must stay open)
@@ -338,6 +348,16 @@ class _HomeScreenState extends State<HomeScreen> {
             icon: 'ic_notification',
           ),
         );
+
+        // Skip if tomorrow's alarm already exists.
+        final existing = await Alarm.getAlarm(_alarmId);
+        if (existing == settings) {
+          _debug(
+            "Alarm already exists, skipping schedule. ${settings.toString()}",
+          );
+          return;
+        }
+
         await Alarm.set(alarmSettings: settings);
       }
       // End Alarm Method ***/
@@ -363,11 +383,13 @@ class _HomeScreenState extends State<HomeScreen> {
     } else if (Platform.isAndroid) {
       // Notification Method
       if (ANDROID_USE_NOTIF) {
-        await _notifications.cancel(id: _alarmId);
+        //await _notifications.cancel(id: _alarmId);
+        await _notifications.cancelAll();
       }
       // Alarm Method
       if (ANDROID_USE_ALARM) {
-        await Alarm.stop(_alarmId);
+        //await Alarm.stop(_alarmId);
+        await Alarm.stopAll();
       }
     }
     _showSnack('Alarm Cancelled');