diff --git a/libs/bpm-core/src/lib/workflow-engine/workflow-engine.service.spec.ts b/libs/bpm-core/src/lib/workflow-engine/workflow-engine.service.spec.ts
index dd2aff6..093825c 100644
--- a/libs/bpm-core/src/lib/workflow-engine/workflow-engine.service.spec.ts
+++ b/libs/bpm-core/src/lib/workflow-engine/workflow-engine.service.spec.ts
@@ -3189,6 +3189,72 @@ describe('WorkflowEngineService', () => {
     );
   });
 
+  it('returns a cancelled ad-hoc directive that still resolves its GraphQL getters', async (): Promise<void> => {
+    const fixture = createServiceFixture({
+      currentVersionId: 'template-version-1',
+      formVersionStatus: FormDefinitionVersionStatusEnum.PUBLISHED,
+      processAdhocDirectives: [
+        createAdhocDirective({
+          createdByMemberId: 'member-finance',
+          id: 'directive-cancel-1',
+          status: AdhocDirectiveStatusEnum.PENDING,
+          targetValue: {
+            kind: AdhocTargetKindEnum.MEMBER,
+            memberIds: ['member-x'],
+          },
+          type: AdhocDirectiveTypeEnum.COUNTERSIGN,
+        }),
+      ],
+      processWorkflowSnapshot: createLinearUserTaskWorkflow(),
+      templateVersionStatus: ApprovalTemplateVersionStatusEnum.PUBLISHED,
+    });
+
+    const cancelled = await fixture.service.cancelAdhocDirective({
+      cancelledByMemberId: 'member-finance',
+      directiveId: 'directive-cancel-1',
+    });
+
+    expect(cancelled.status).toBe(AdhocDirectiveStatusEnum.CANCELLED);
+    // `targetValueJson` is a non-nullable GraphQL field backed by a prototype
+    // getter, so the resolver only survives if the saved value is still an
+    // entity instance. Spreading the row into a plain object drops the getter
+    // and the mutation fails with an opaque INTERNAL_SERVER_ERROR *after* the
+    // cancellation has already been written, which reads to the approver as
+    // "the withdraw failed" even though it succeeded.
+    expect(cancelled).toBeInstanceOf(AdhocDirectiveEntity);
+    expect(cancelled.targetValueJson).toBe(
+      JSON.stringify({
+        kind: AdhocTargetKindEnum.MEMBER,
+        memberIds: ['member-x'],
+      }),
+    );
+  });
+
+  it('returns a cancelled instance that still resolves its GraphQL getters', async (): Promise<void> => {
+    const fixture = createServiceFixture({
+      currentVersionId: 'template-version-1',
+      formVersionStatus: FormDefinitionVersionStatusEnum.PUBLISHED,
+      processFormData: { amount: 1200 },
+      processWorkflowSnapshot: createLinearUserTaskWorkflow(),
+      templateVersionStatus: ApprovalTemplateVersionStatusEnum.PUBLISHED,
+    });
+
+    const cancelled = await fixture.service.cancelApprovalInstance({
+      cancelledByMemberId: 'member-001',
+      comment: null,
+      instanceId: 'instance-1',
+    });
+
+    expect(cancelled.state).toBe(ApprovalInstanceStateEnum.CANCELLED);
+    // `ApprovalInstance` exposes five getter-backed JSON fields, all of them
+    // non-nullable. Spreading the row into a plain object drops every one, so
+    // the withdrawal is committed and the mutation still fails with an opaque
+    // INTERNAL_SERVER_ERROR — the initiator sees "cancel failed" on a case
+    // that is already cancelled.
+    expect(cancelled).toBeInstanceOf(ApprovalInstanceEntity);
+    expect(cancelled.formDataJson).toBe(JSON.stringify({ amount: 1200 }));
+  });
+
   it('dispatches ad-hoc completion notifications on reject and cancels pending flow directives', async (): Promise<void> => {
     const fixture = createServiceFixture({
       currentVersionId: 'template-version-1',
@@ -3623,19 +3689,35 @@ function createServiceFixture({
       ),
       findOne: jest.fn(() =>
         Promise.resolve(
-          savedInstance ??
-            createApprovalInstance({
-              formData: processFormData,
-              formDataOptionSnapshot: processOptionSnapshot,
-              formDefinitionSnapshot: processFormDefinitionSnapshot,
-              state: instanceState,
-              updatedAt: transactionalInstanceUpdatedAt,
-              workflowSnapshot: processWorkflowSnapshot,
-            }),
+          // A row read back from the database is an entity whatever shape the
+          // caller last handed to `save`, so it is rehydrated here. Only
+          // `save` reports the shape it was actually given.
+          savedInstance
+            ? Object.assign(createApprovalInstance(), savedInstance)
+            : createApprovalInstance({
+                formData: processFormData,
+                formDataOptionSnapshot: processOptionSnapshot,
+                formDefinitionSnapshot: processFormDefinitionSnapshot,
+                state: instanceState,
+                updatedAt: transactionalInstanceUpdatedAt,
+                workflowSnapshot: processWorkflowSnapshot,
+              }),
         ),
       ),
       save: jest.fn((entity: ApprovalInstanceEntity) => {
-        savedInstance = Object.assign(createApprovalInstance(), entity);
+        // The saved row keeps the prototype it arrived with. Rebuilding it as
+        // `Object.assign(createApprovalInstance(), entity)` handed back an
+        // entity even when the caller had spread the row into a plain object,
+        // which hid exactly the regression the cancel paths guard against:
+        // the getter-backed `*Json` fields the GraphQL schema exposes live on
+        // the prototype, so a plain object fails the mutation at resolve time.
+        savedInstance = Object.assign(
+          Object.create(
+            Object.getPrototypeOf(entity) as object,
+          ) as ApprovalInstanceEntity,
+          createApprovalInstance(),
+          entity,
+        );
 
         return Promise.resolve(savedInstance);
       }),
diff --git a/libs/bpm-core/src/lib/workflow-engine/workflow-engine.service.ts b/libs/bpm-core/src/lib/workflow-engine/workflow-engine.service.ts
index abad75e..e17a379 100644
--- a/libs/bpm-core/src/lib/workflow-engine/workflow-engine.service.ts
+++ b/libs/bpm-core/src/lib/workflow-engine/workflow-engine.service.ts
@@ -939,11 +939,15 @@ export class WorkflowEngineService {
           instanceId: instance.id,
           manager,
         });
-        const cancelledInstance = await instanceRepository.save({
-          ...instance,
-          completedAt: cancelledAt,
-          state: ApprovalInstanceStateEnum.CANCELLED,
-        });
+        // Same prototype-preserving reason as `cancelAdhocDirective`: this
+        // entity is returned to the resolver and `ApprovalInstance` exposes
+        // five getter-backed JSON fields.
+        const cancelledInstance = await instanceRepository.save(
+          Object.assign(new ApprovalInstanceEntity(), instance, {
+            completedAt: cancelledAt,
+            state: ApprovalInstanceStateEnum.CANCELLED,
+          }),
+        );
 
         await this.dispatchAdhocCompletionNotifications(
           manager,
@@ -1317,10 +1321,16 @@ export class WorkflowEngineService {
           );
         }
 
-        const cancelledDirective = await directiveRepository.save({
-          ...directive,
-          status: AdhocDirectiveStatusEnum.CANCELLED,
-        });
+        // Assigning onto a fresh entity keeps the prototype, so the row handed
+        // back to the resolver still carries the getters the GraphQL schema
+        // exposes (e.g. `targetValueJson`). Spreading it into a plain object
+        // drops them, and the mutation then fails with an opaque
+        // INTERNAL_SERVER_ERROR *after* the cancellation has been committed.
+        const cancelledDirective = await directiveRepository.save(
+          Object.assign(new AdhocDirectiveEntity(), directive, {
+            status: AdhocDirectiveStatusEnum.CANCELLED,
+          }),
+        );
 
         await this.recordAdhocDirectiveActivity(
           manager,