diff --git a/extensions/slack/src/monitor/message-handler/dispatch.ts b/extensions/slack/src/monitor/message-handler/dispatch.ts
index 802960deda2..861ffe8dceb 100644
--- a/extensions/slack/src/monitor/message-handler/dispatch.ts
+++ b/extensions/slack/src/monitor/message-handler/dispatch.ts
@@ -190,14 +190,17 @@ export async function dispatchPreparedSlackMessage(prepared: PreparedSlackMessag
     replyToMode: prepared.replyToMode,
   });
 
+  const reactionMessageTs = prepared.ackReactionMessageTs;
   const messageTs = message.ts ?? message.event_ts;
   const incomingThreadTs = message.thread_ts;
   let didSetStatus = false;
   const statusReactionsEnabled =
-    Boolean(prepared.ackReactionPromise) && cfg.messages?.statusReactions?.enabled !== false;
+    Boolean(prepared.ackReactionPromise) &&
+    Boolean(reactionMessageTs) &&
+    cfg.messages?.statusReactions?.enabled !== false;
   const slackStatusAdapter: StatusReactionAdapter = {
     setReaction: async (emoji) => {
-      await reactSlackMessage(message.channel, message.ts ?? "", toSlackEmojiName(emoji), {
+      await reactSlackMessage(message.channel, reactionMessageTs ?? "", toSlackEmojiName(emoji), {
         token: ctx.botToken,
         client: ctx.app.client,
       }).catch((err) => {
@@ -208,7 +211,7 @@ export async function dispatchPreparedSlackMessage(prepared: PreparedSlackMessag
       });
     },
     removeReaction: async (emoji) => {
-      await removeSlackReaction(message.channel, message.ts ?? "", toSlackEmojiName(emoji), {
+      await removeSlackReaction(message.channel, reactionMessageTs ?? "", toSlackEmojiName(emoji), {
         token: ctx.botToken,
         client: ctx.app.client,
       }).catch((err) => {
diff --git a/extensions/slack/src/monitor/message-handler/prepare.test.ts b/extensions/slack/src/monitor/message-handler/prepare.test.ts
index a57614afaeb..7da7786a943 100644
--- a/extensions/slack/src/monitor/message-handler/prepare.test.ts
+++ b/extensions/slack/src/monitor/message-handler/prepare.test.ts
@@ -214,6 +214,33 @@ describe("slack prepareSlackMessage inbound contract", () => {
     expectInboundContextContract(prepared!.ctxPayload as any);
   });
 
+  it("does not enable Slack status reactions when the message timestamp is missing", async () => {
+    const slackCtx = createInboundSlackCtx({
+      cfg: {
+        messages: {
+          ackReaction: "👀",
+          ackReactionScope: "all",
+          statusReactions: { enabled: true },
+        },
+        channels: { slack: { enabled: true } },
+      } as OpenClawConfig,
+    });
+    // oxlint-disable-next-line typescript/no-explicit-any
+    slackCtx.resolveUserName = async () => ({ name: "Alice" }) as any;
+
+    const prepared = await prepareMessageWith(slackCtx, defaultAccount, {
+      channel: "D123",
+      channel_type: "im",
+      user: "U1",
+      text: "hi",
+      event_ts: "1.000",
+    } as SlackMessageEvent);
+
+    expect(prepared).toBeTruthy();
+    expect(prepared?.ackReactionMessageTs).toBeUndefined();
+    expect(prepared?.ackReactionPromise).toBeNull();
+  });
+
   it("includes forwarded shared attachment text in raw body", async () => {
     const prepared = await prepareWithDefaultCtx(
       createSlackMessage({
diff --git a/extensions/slack/src/monitor/message-handler/prepare.ts b/extensions/slack/src/monitor/message-handler/prepare.ts
index 1d43c1324e1..a571f5e8ce7 100644
--- a/extensions/slack/src/monitor/message-handler/prepare.ts
+++ b/extensions/slack/src/monitor/message-handler/prepare.ts
@@ -556,7 +556,9 @@ export async function prepareSlackMessage(params: {
 
   const ackReactionMessageTs = message.ts;
   const statusReactionsWillHandle =
-    cfg.messages?.statusReactions?.enabled !== false && shouldAckReaction();
+    Boolean(ackReactionMessageTs) &&
+    cfg.messages?.statusReactions?.enabled !== false &&
+    shouldAckReaction();
   const ackReactionPromise =
     !statusReactionsWillHandle && shouldAckReaction() && ackReactionMessageTs && ackReactionValue
       ? reactSlackMessage(message.channel, ackReactionMessageTs, ackReactionValue, {
diff --git a/src/channels/status-reactions.slack-lifecycle.test.ts b/src/channels/status-reactions.slack-lifecycle.test.ts
index 52a5250b01b..54918267153 100644
--- a/src/channels/status-reactions.slack-lifecycle.test.ts
+++ b/src/channels/status-reactions.slack-lifecycle.test.ts
@@ -1,4 +1,4 @@
-import { beforeEach, describe, expect, it, vi } from "vitest";
+import { afterEach, beforeEach, describe, expect, it, vi } from "vitest";
 import {
   createStatusReactionController,
   DEFAULT_EMOJIS,
@@ -36,6 +36,10 @@ describe("Slack status reaction lifecycle", () => {
     vi.useFakeTimers();
   });
 
+  afterEach(() => {
+    vi.useRealTimers();
+  });
+
   it("queued -> thinking -> tool -> done -> clear", async () => {
     const { adapter, active, log } = createSlackMockAdapter();
     const ctrl = createStatusReactionController({