diff --git a/api_tests/package.json b/api_tests/package.json
index cc58c83e9..cacd476ea 100644
--- a/api_tests/package.json
+++ b/api_tests/package.json
@@ -27,7 +27,7 @@
     "eslint": "^9.8.0",
     "eslint-plugin-prettier": "^5.1.3",
     "jest": "^29.5.0",
-    "lemmy-js-client": "0.20.0-alpha.4",
+    "lemmy-js-client": "0.20.0-alpha.11",
     "prettier": "^3.2.5",
     "ts-jest": "^29.1.0",
     "typescript": "^5.5.4",
diff --git a/api_tests/pnpm-lock.yaml b/api_tests/pnpm-lock.yaml
index 0b6a19f81..f72450015 100644
--- a/api_tests/pnpm-lock.yaml
+++ b/api_tests/pnpm-lock.yaml
@@ -30,8 +30,8 @@ importers:
         specifier: ^29.5.0
         version: 29.7.0(@types/node@22.3.0)
       lemmy-js-client:
-        specifier: 0.20.0-alpha.4
-        version: 0.20.0-alpha.4
+        specifier: 0.20.0-alpha.11
+        version: 0.20.0-alpha.11
       prettier:
         specifier: ^3.2.5
         version: 3.3.3
@@ -1175,8 +1175,8 @@ packages:
     resolution: {integrity: sha512-eTIzlVOSUR+JxdDFepEYcBMtZ9Qqdef+rnzWdRZuMbOywu5tO2w2N7rqjoANZ5k9vywhL6Br1VRjUIgTQx4E8w==}
     engines: {node: '>=6'}
 
-  lemmy-js-client@0.20.0-alpha.4:
-    resolution: {integrity: sha512-MuVE8u/IFz59ks2vxOUXMRU8x6SIz3Keu4zRhmhNt+n+gI25JAggsTDrtxVCBtrqBhFEe+a3PdXdwm+fXbs0Dw==}
+  lemmy-js-client@0.20.0-alpha.11:
+    resolution: {integrity: sha512-iRSG4xHMjPDIreQqVIoJ5JrMY71uk07G0Zbgyf068xKbib22J3+i1x/XgCTs6tiHlqTnw1Ig/KRq7p7qJoA4uw==}
 
   leven@3.1.0:
     resolution: {integrity: sha512-qsda+H8jTaUaN/x5vzW2rzc+8Rw4TAQ/4KjB46IwK5VH+IlVeeeje/EoZRpiXvIqjFgK84QffqPztGI3VBLG1A==}
@@ -3107,7 +3107,7 @@ snapshots:
 
   kleur@3.0.3: {}
 
-  lemmy-js-client@0.20.0-alpha.4: {}
+  lemmy-js-client@0.20.0-alpha.11: {}
 
   leven@3.1.0: {}
 
diff --git a/api_tests/src/comment.spec.ts b/api_tests/src/comment.spec.ts
index 8c3a23ab5..c18469e33 100644
--- a/api_tests/src/comment.spec.ts
+++ b/api_tests/src/comment.spec.ts
@@ -92,7 +92,7 @@ test("Create a comment", async () => {
 
 test("Create a comment in a non-existent post", async () => {
   await expect(createComment(alpha, -1)).rejects.toStrictEqual(
-    Error("couldnt_find_post"),
+    Error("not_found"),
   );
 });
 
@@ -143,7 +143,7 @@ test("Delete a comment", async () => {
     await waitUntil(
       () =>
         resolveComment(gamma, commentRes.comment_view.comment).catch(e => e),
-      r => r.message !== "couldnt_find_object",
+      r => r.message !== "not_found",
     )
   ).comment;
   if (!gammaComment) {
@@ -161,13 +161,13 @@ test("Delete a comment", async () => {
   // Make sure that comment is undefined on beta
   await waitUntil(
     () => resolveComment(beta, commentRes.comment_view.comment).catch(e => e),
-    e => e.message == "couldnt_find_object",
+    e => e.message == "not_found",
   );
 
   // Make sure that comment is undefined on gamma after delete
   await waitUntil(
     () => resolveComment(gamma, commentRes.comment_view.comment).catch(e => e),
-    e => e.message === "couldnt_find_object",
+    e => e.message === "not_found",
   );
 
   // Test undeleting the comment
@@ -182,7 +182,7 @@ test("Delete a comment", async () => {
   let betaComment2 = (
     await waitUntil(
       () => resolveComment(beta, commentRes.comment_view.comment).catch(e => e),
-      e => e.message !== "couldnt_find_object",
+      e => e.message !== "not_found",
     )
   ).comment;
   expect(betaComment2?.comment.deleted).toBe(false);
diff --git a/api_tests/src/community.spec.ts b/api_tests/src/community.spec.ts
index d8aa6cad6..77b68e2fc 100644
--- a/api_tests/src/community.spec.ts
+++ b/api_tests/src/community.spec.ts
@@ -527,12 +527,12 @@ test("Content in local-only community doesn't federate", async () => {
   // cant resolve the community from another instance
   await expect(
     resolveCommunity(beta, communityRes.actor_id),
-  ).rejects.toStrictEqual(Error("couldnt_find_object"));
+  ).rejects.toStrictEqual(Error("not_found"));
 
   // create a post, also cant resolve it
   let postRes = await createPost(alpha, communityRes.id);
   await expect(resolvePost(beta, postRes.post_view.post)).rejects.toStrictEqual(
-    Error("couldnt_find_object"),
+    Error("not_found"),
   );
 });
 
diff --git a/api_tests/src/post.spec.ts b/api_tests/src/post.spec.ts
index e059d4585..bb0416057 100644
--- a/api_tests/src/post.spec.ts
+++ b/api_tests/src/post.spec.ts
@@ -125,12 +125,12 @@ test("Create a post", async () => {
   // Delta only follows beta, so it should not see an alpha ap_id
   await expect(
     resolvePost(delta, postRes.post_view.post),
-  ).rejects.toStrictEqual(Error("couldnt_find_object"));
+  ).rejects.toStrictEqual(Error("not_found"));
 
   // Epsilon has alpha blocked, it should not see the alpha post
   await expect(
     resolvePost(epsilon, postRes.post_view.post),
-  ).rejects.toStrictEqual(Error("couldnt_find_object"));
+  ).rejects.toStrictEqual(Error("not_found"));
 
   // remove added allow/blocklists
   editSiteForm.allowed_instances = [];
@@ -140,9 +140,7 @@ test("Create a post", async () => {
 });
 
 test("Create a post in a non-existent community", async () => {
-  await expect(createPost(alpha, -2)).rejects.toStrictEqual(
-    Error("couldnt_find_community"),
-  );
+  await expect(createPost(alpha, -2)).rejects.toStrictEqual(Error("not_found"));
 });
 
 test("Unlike a post", async () => {