diff --git a/.changelog/28005.txt b/.changelog/28005.txt
new file mode 100644
index 00000000000..df19744dbfd
--- /dev/null
+++ b/.changelog/28005.txt
@@ -0,0 +1,3 @@
+```release-note:bug
+ui: Fix service detail page not rendering
+```
diff --git a/ui/app/adapters/watchable.js b/ui/app/adapters/watchable.js
index bb1f1fb656e..d3fa145c68a 100644
--- a/ui/app/adapters/watchable.js
+++ b/ui/app/adapters/watchable.js
@@ -218,9 +218,36 @@ export default class Watchable extends ApplicationAdapter {
             json,
           );
           if (replace) {
-            store.unloadAll(relationship.type);
+            // Capture existing record IDs before pushing new data.
+            // We must push first so that the relationship's LID references are
+            // updated before any old records are removed. Calling
+            // store.unloadAll() first leaves dangling LID references in the
+            // hasMany relationship state, which causes Ember Data 4.12+ to
+            // throw "Cannot create a record ... as no resource data exists"
+            // when the relationship is accessed.
+            const existingIds = store
+              .peekAll(relationship.type)
+              .map((r) => r.id);
+            const newIds = new Set(
+              (normalizedData.data || []).map((r) => r.id),
+            );
+
+            store.push(normalizedData);
+
+            // Remove records that were not present in the new payload using
+            // removeRecord, which safely unlinks the record from all of its
+            // relationships before unloading it from the store.
+            existingIds.forEach((id) => {
+              if (!newIds.has(id)) {
+                const record = store.peekRecord(relationship.type, id);
+                if (record) {
+                  removeRecord(store, record);
+                }
+              }
+            });
+          } else {
+            store.push(normalizedData);
           }
-          store.push(normalizedData);
         },
         (error) => {
           if (error instanceof AbortError || error.name === 'AbortError') {
diff --git a/ui/tests/unit/adapters/job-test.js b/ui/tests/unit/adapters/job-test.js
index 3e88c58b6da..06fb4c0ba01 100644
--- a/ui/tests/unit/adapters/job-test.js
+++ b/ui/tests/unit/adapters/job-test.js
@@ -278,6 +278,73 @@ module('Unit | Adapter | Job', function (hooks) {
     );
   });
 
+  test('reloadRelationship with replace:true pushes new records before removing stale ones, preventing dangling LID references', async function (assert) {
+    await this.initializeUI();
+
+    // Create two services for job-1 in mirage
+    this.server.create('service', {
+      id: 'svc-keep',
+      jobId: 'job-1',
+      namespace: 'default',
+    });
+    this.server.create('service', {
+      id: 'svc-remove',
+      jobId: 'job-1',
+      namespace: 'default',
+    });
+
+    // Load the job and trigger the initial services relationship load
+    const job = await this.store.findRecord(
+      'job',
+      JSON.stringify(['job-1', 'default']),
+    );
+    await job.services;
+    await settled();
+
+    assert.strictEqual(
+      this.store.peekAll('service').length,
+      2,
+      'Initially 2 services are in the store',
+    );
+
+    // Simulate a server-side change: svc-remove is gone from the server
+    this.server.db.services.remove('svc-remove');
+
+    // Reload the services relationship with replace: true
+    await this.store.adapterFor('job').reloadRelationship(job, 'services', {
+      replace: true,
+    });
+    await settled();
+
+    assert.notOk(
+      this.store.peekRecord('service', 'svc-remove'),
+      'svc-remove is removed from the store after the replace reload',
+    );
+    assert.ok(
+      this.store.peekRecord('service', 'svc-keep'),
+      'svc-keep is still in the store after the replace reload',
+    );
+
+    // Critically, accessing the job's services relationship must not throw
+    // the "Cannot create a record ... as no resource data exists" error that
+    // Ember Data 4.12 raises when a hasMany relationship still holds a dangling
+    // LID for a record that was removed via store.unloadAll().
+    let errorThrown = null;
+    try {
+      const currentServices = job.hasMany('services').value();
+      if (currentServices) {
+        currentServices.forEach((s) => void s.serviceName);
+      }
+    } catch (e) {
+      errorThrown = e;
+    }
+    assert.strictEqual(
+      errorThrown,
+      null,
+      'Accessing job.services after a replace reload does not throw',
+    );
+  });
+
   test('findAll can be canceled', async function (assert) {
     await this.initializeUI();
 
diff --git a/ui/tests/unit/serializers/network-test.js b/ui/tests/unit/serializers/network-test.js
index 18049d93ea8..77e8f8803cd 100644
--- a/ui/tests/unit/serializers/network-test.js
+++ b/ui/tests/unit/serializers/network-test.js
@@ -44,4 +44,15 @@ module('Unit | Serializer | Network', function (hooks) {
       undefined,
     );
   });
+
+  test('missing IP does not throw', async function (assert) {
+    const original = {
+      ReservedPorts: [{ Label: 'http', Value: 80 }],
+    };
+
+    assert.deepEqual(
+      this.subject().normalize(NetworkModel, original).data.attributes.ip,
+      undefined,
+    );
+  });
 });
diff --git a/ui/tests/unit/serializers/port-test.js b/ui/tests/unit/serializers/port-test.js
index 0e680044731..21c45039c20 100644
--- a/ui/tests/unit/serializers/port-test.js
+++ b/ui/tests/unit/serializers/port-test.js
@@ -1,5 +1,5 @@
 /**
- * Copyright IBM Corp. 2015, 2025
+ * Copyright IBM Corp. 2015, 2026
  * SPDX-License-Identifier: BUSL-1.1
  */