diff --git a/functions/anonymizeMovements.js b/functions/anonymizeMovements.js
index 528b740f..007369a6 100644
--- a/functions/anonymizeMovements.js
+++ b/functions/anonymizeMovements.js
@@ -13,14 +13,12 @@ const PII_FIELDS = [
   'phone',
   'memberNr',
   'immatriculation',
-  'aircraftType',
-  'mtow',
   'remarks',
-  'carriageVoucher',
   'createdBy',
   'createdBy_orderKey',
   'customsFormId',
   'customsFormUrl',
+  'privacyPolicyAcceptedAt',
 ];
 
 function getAnonymizationUpdates(snapshot, cutoffIso) {
@@ -35,6 +33,9 @@ function getAnonymizationUpdates(snapshot, cutoffIso) {
           updates[`${child.key}/${field}`] = null;
         }
       });
+      if (val.paymentMethod && val.paymentMethod.invoiceRecipientName !== undefined) {
+        updates[`${child.key}/paymentMethod/invoiceRecipientName`] = null;
+      }
       updates[`${child.key}/anonymized`] = true;
     }
   });
diff --git a/functions/anonymizeMovements.spec.js b/functions/anonymizeMovements.spec.js
index e5de6f88..f97f2d61 100644
--- a/functions/anonymizeMovements.spec.js
+++ b/functions/anonymizeMovements.spec.js
@@ -81,6 +81,7 @@ describe('anonymizeMovements', () => {
         remarks: 'test',
         createdBy: 'uid1',
         createdBy_orderKey: 'uid1_123',
+        privacyPolicyAcceptedAt: '2023-01-15T09:55:00.000Z',
         location: 'LSZT',
         flightType: 'private',
         negativeTimestamp: -1673776800000,
@@ -103,13 +104,15 @@ describe('anonymizeMovements', () => {
     expect(departureUpdates['mov1/phone']).toBeNull();
     expect(departureUpdates['mov1/memberNr']).toBeNull();
     expect(departureUpdates['mov1/immatriculation']).toBeNull();
-    expect(departureUpdates['mov1/aircraftType']).toBeNull();
-    expect(departureUpdates['mov1/mtow']).toBeNull();
     expect(departureUpdates['mov1/remarks']).toBeNull();
     expect(departureUpdates['mov1/createdBy']).toBeNull();
     expect(departureUpdates['mov1/createdBy_orderKey']).toBeNull();
+    expect(departureUpdates['mov1/privacyPolicyAcceptedAt']).toBeNull();
     expect(departureUpdates['mov1/anonymized']).toBe(true);
 
+    // Non-PII fields are preserved
+    expect(departureUpdates['mov1/aircraftType']).toBeUndefined();
+    expect(departureUpdates['mov1/mtow']).toBeUndefined();
     expect(departureUpdates['mov1/location']).toBeUndefined();
     expect(departureUpdates['mov1/flightType']).toBeUndefined();
     expect(departureUpdates['mov1/dateTime']).toBeUndefined();
@@ -147,13 +150,66 @@ describe('anonymizeMovements', () => {
     expect(updates['mov1/anonymized']).toBe(true);
 
     // Fields absent from the record must not appear in the update object
-    expect(updates['mov1/carriageVoucher']).toBeUndefined();
     expect(updates['mov1/customsFormId']).toBeUndefined();
     expect(updates['mov1/customsFormUrl']).toBeUndefined();
     expect(updates['mov1/email']).toBeUndefined();
     expect(updates['mov1/phone']).toBeUndefined();
   });
 
+  it('should anonymize invoiceRecipientName from paymentMethod', async () => {
+    mockRefData['/settings/movementRetentionDays'] = createValueSnapshot(730);
+
+    const snapshot = createSnapshot({
+      'mov1': {
+        dateTime: '2023-01-15T10:00:00.000Z',
+        firstname: 'Hans',
+        lastname: 'Muster',
+        paymentMethod: {
+          method: 'invoice',
+          invoiceRecipientName: 'Fluggruppe Thurgau',
+        },
+        location: 'LSZT',
+      },
+    });
+
+    mockRefData['/departures'] = { forEach: () => {} };
+    mockRefData['/arrivals'] = snapshot;
+
+    const { scheduledAnonymizeMovements } = require('./anonymizeMovements');
+    await scheduledAnonymizeMovements();
+
+    expect(mockUpdate).toHaveBeenCalledTimes(1);
+
+    const updates = mockUpdate.mock.calls[0][0];
+    expect(updates['mov1/paymentMethod/invoiceRecipientName']).toBeNull();
+    // payment method itself is preserved
+    expect(updates['mov1/paymentMethod']).toBeUndefined();
+  });
+
+  it('should not add paymentMethod update when invoiceRecipientName is absent', async () => {
+    mockRefData['/settings/movementRetentionDays'] = createValueSnapshot(730);
+
+    const snapshot = createSnapshot({
+      'mov1': {
+        dateTime: '2023-01-15T10:00:00.000Z',
+        firstname: 'Hans',
+        paymentMethod: { method: 'cash' },
+        location: 'LSZT',
+      },
+    });
+
+    mockRefData['/departures'] = { forEach: () => {} };
+    mockRefData['/arrivals'] = snapshot;
+
+    const { scheduledAnonymizeMovements } = require('./anonymizeMovements');
+    await scheduledAnonymizeMovements();
+
+    expect(mockUpdate).toHaveBeenCalledTimes(1);
+
+    const updates = mockUpdate.mock.calls[0][0];
+    expect(updates['mov1/paymentMethod/invoiceRecipientName']).toBeUndefined();
+  });
+
   it('should skip already anonymized movements', async () => {
     mockRefData['/settings/movementRetentionDays'] = createValueSnapshot(730);
 
diff --git a/src/util/LandingsReport.ts b/src/util/LandingsReport.ts
index bf8ae459..cc5874be 100644
--- a/src/util/LandingsReport.ts
+++ b/src/util/LandingsReport.ts
@@ -68,6 +68,8 @@ class LandingsReport {
       const arrival = firebaseToLocal(record.val());
       const { immatriculation, mtow, landingCount } = arrival;
 
+      if (!immatriculation) return;
+
       if (!map[immatriculation]) {
         map[immatriculation] = {
           immatriculation,
@@ -90,7 +92,7 @@ class LandingsReport {
     Object.keys(map).forEach(key => {
       arr.push(map[key]);
     });
-    arr.sort((a1, a2) => a1.immatriculation.localeCompare(a2.immatriculation));
+    arr.sort((a1, a2) => (a1.immatriculation || '').localeCompare(a2.immatriculation || ''));
 
     return arr;
   }
diff --git a/src/util/movements.spec.ts b/src/util/movements.spec.ts
index 5a518e56..715e5206 100644
--- a/src/util/movements.spec.ts
+++ b/src/util/movements.spec.ts
@@ -241,6 +241,55 @@ describe('util', () => {
       });
     });
 
+    describe('sorting with null immatriculation (anonymized records)', () => {
+      it('compareDescending does not crash when immatriculation is null', () => {
+        const a = {
+          date: '2016-03-08',
+          time: '08:30',
+          immatriculation: null,
+        };
+        const b = {
+          date: '2016-03-08',
+          time: '08:30',
+          immatriculation: 'HB-KFW',
+        };
+
+        expect(() => compareDescending(a as any, b as any)).not.toThrow();
+        expect(compareDescending(a as any, b as any)).toBe(-1);
+      });
+
+      it('compareAscending does not crash when immatriculation is null', () => {
+        const a = {
+          date: '2016-03-08',
+          time: '08:30',
+          immatriculation: 'HB-KFW',
+        };
+        const b = {
+          date: '2016-03-08',
+          time: '08:30',
+          immatriculation: null,
+        };
+
+        expect(() => compareAscending(a as any, b as any)).not.toThrow();
+        expect(compareAscending(a as any, b as any)).toBe(1);
+      });
+
+      it('compareDescending returns 0 when both immatriculations are null', () => {
+        const a = {
+          date: '2016-03-08',
+          time: '08:30',
+          immatriculation: null,
+        };
+        const b = {
+          date: '2016-03-08',
+          time: '08:30',
+          immatriculation: null,
+        };
+
+        expect(compareDescending(a as any, b as any)).toBe(0);
+      });
+    });
+
     describe('transferValues', () => {
       it('transfers values which are not undefined and not null', () => {
         const source = {
diff --git a/src/util/movements.ts b/src/util/movements.ts
index 9c6fe833..c4b966a5 100644
--- a/src/util/movements.ts
+++ b/src/util/movements.ts
@@ -129,7 +129,7 @@ export function compareDescending(a: Movement, b: Movement): number {
     return dateCompare;
   }
 
-  return a.immatriculation.localeCompare(b.immatriculation);
+  return (a.immatriculation || '').localeCompare(b.immatriculation || '');
 }
 
 /**
@@ -144,5 +144,5 @@ export function compareAscending(a: Movement, b: Movement): number {
     return dateCompare;
   }
 
-  return a.immatriculation.localeCompare(b.immatriculation);
+  return (a.immatriculation || '').localeCompare(b.immatriculation || '');
 }