diff --git a/src/components/EventForm.vue b/src/components/EventForm.vue
index e35c9dc..00a6c5f 100644
--- a/src/components/EventForm.vue
+++ b/src/components/EventForm.vue
@@ -167,7 +167,7 @@ export default {
   },
   watch: {
     event(newVal) {
-      this.eventData = { ...newVal };
+      this.eventData = this.normalizeEventForForm(newVal);
       this.determineDateMode();
       if (newVal && typeof newVal.__newsletterDateMode === 'string') {
         this.dateMode = newVal.__newsletterDateMode;
@@ -226,13 +226,14 @@ export default {
     formatTime,
     async saveEvent() {
       try {
+        const dayOfWeekValue = this.extractDayOfWeekValue(this.eventData.dayOfWeek);
         const basePayload = {
           ...this.eventData,
           eventTypeId: this.selectedEventType ? this.selectedEventType.id : null,
           institution_id: this.selectedInstitution ? this.selectedInstitution.id : null,
           event_place_id: this.selectedEventPlace ? this.selectedEventPlace.id : null,
           contactPersonIds: this.selectedContactPersons.map(person => person.id),
-          dayOfWeek: this.eventData.dayOfWeek ? this.eventData.dayOfWeek.value ?? -1 : -1,
+          dayOfWeek: dayOfWeekValue,
           relatedImage: this.assignedImage,
           alsoOnHomepage: this.onHomepage ? 1 : 0
         };
@@ -295,16 +296,44 @@ export default {
       }
     },
     determineDateMode() {
-      if (this.eventData.date && this.eventData.dayOfWeek) {
-        this.dateMode = 'interval';
-      } else if (this.eventData.date) {
+      // Bei bestehenden Events hat dayOfWeek oft einen Wert, obwohl "Datum" gemeint ist.
+      // Deshalb hat fixes Datum Vorrang vor Intervall.
+      if (this.eventData.date) {
         this.dateMode = 'date';
-      } else if (this.eventData.dayOfWeek) {
+      } else if (this.extractDayOfWeekValue(this.eventData.dayOfWeek) > -1) {
         this.dateMode = 'weekday';
       } else {
         this.dateMode = 'date';
       }
     },
+    normalizeEventForForm(event) {
+      const normalized = { ...(event || {}) };
+      if (typeof normalized.date === 'string') {
+        normalized.date = normalized.date.split('T')[0];
+      }
+      const dayValue = this.extractDayOfWeekValue(normalized.dayOfWeek);
+      if (dayValue > -1) {
+        const mappedValue = dayValue === 0 ? 7 : dayValue;
+        normalized.dayOfWeek =
+          this.weekdays.find((d) => d.value === mappedValue) || null;
+      } else {
+        normalized.dayOfWeek = null;
+      }
+      return normalized;
+    },
+    extractDayOfWeekValue(dayOfWeek) {
+      if (dayOfWeek === null || dayOfWeek === undefined || dayOfWeek === '') {
+        return -1;
+      }
+      if (typeof dayOfWeek === 'object') {
+        if (dayOfWeek.value === null || dayOfWeek.value === undefined || dayOfWeek.value === '') {
+          return -1;
+        }
+        return Number(dayOfWeek.value);
+      }
+      const parsed = Number(dayOfWeek);
+      return Number.isFinite(parsed) ? parsed : -1;
+    },
     async fetchImageFilename() {
       try {
         const response = await axios.get('/image/' + this.assignedImage);