diff --git a/CHANGELOG.md b/CHANGELOG.md
index 2a87df0e76f..2377f696583 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -324,6 +324,7 @@ Docs: https://docs.openclaw.ai
 - Telegram/preview-final edit idempotence: treat `message is not modified` errors during preview finalization as delivered so partial-stream final replies do not fall back to duplicate sends. Landed from contributor PR #34983 by @HOYALIM. Thanks @HOYALIM.
 - Telegram/DM streaming transport parity: use message preview transport for all DM streaming lanes so final delivery can edit the active preview instead of sending duplicate finals. Landed from contributor PR #38906 by @gambletan. Thanks @gambletan.
 - Telegram/send retry safety: retry non-idempotent send paths only for pre-connect failures and make custom retry predicates strict, preventing ambiguous reconnect retries from sending duplicate messages. Landed from contributor PR #34238 by @hal-crackbot. Thanks @hal-crackbot.
+- Discord/DM session-key normalization: rewrite legacy `discord:dm:*` and phantom direct-message `discord:channel:<user>` session keys to `discord:direct:*` when the sender matches, so multi-agent Discord DMs stop falling into empty channel-shaped sessions and resume replying correctly.
 
 ## 2026.3.2
 
diff --git a/src/config/sessions/session-key.test.ts b/src/config/sessions/session-key.test.ts
new file mode 100644
index 00000000000..3bf348d1b76
--- /dev/null
+++ b/src/config/sessions/session-key.test.ts
@@ -0,0 +1,76 @@
+import { describe, expect, it } from "vitest";
+import type { MsgContext } from "../../auto-reply/templating.js";
+import { resolveSessionKey } from "./session-key.js";
+
+function makeCtx(overrides: Partial<MsgContext>): MsgContext {
+  return {
+    Body: "",
+    From: "",
+    To: "",
+    ...overrides,
+  } as MsgContext;
+}
+
+describe("resolveSessionKey", () => {
+  describe("Discord DM session key normalization", () => {
+    it("passes through correct discord:direct keys unchanged", () => {
+      const ctx = makeCtx({
+        SessionKey: "agent:fina:discord:direct:123456",
+        ChatType: "direct",
+        From: "discord:123456",
+        SenderId: "123456",
+      });
+      expect(resolveSessionKey("per-sender", ctx)).toBe("agent:fina:discord:direct:123456");
+    });
+
+    it("migrates legacy discord:dm: keys to discord:direct:", () => {
+      const ctx = makeCtx({
+        SessionKey: "agent:fina:discord:dm:123456",
+        ChatType: "direct",
+        From: "discord:123456",
+        SenderId: "123456",
+      });
+      expect(resolveSessionKey("per-sender", ctx)).toBe("agent:fina:discord:direct:123456");
+    });
+
+    it("fixes phantom discord:channel:USERID keys when sender matches", () => {
+      const ctx = makeCtx({
+        SessionKey: "agent:fina:discord:channel:123456",
+        ChatType: "direct",
+        From: "discord:123456",
+        SenderId: "123456",
+      });
+      expect(resolveSessionKey("per-sender", ctx)).toBe("agent:fina:discord:direct:123456");
+    });
+
+    it("does not rewrite discord:channel: keys for non-direct chats", () => {
+      const ctx = makeCtx({
+        SessionKey: "agent:fina:discord:channel:123456",
+        ChatType: "channel",
+        From: "discord:channel:123456",
+        SenderId: "789",
+      });
+      expect(resolveSessionKey("per-sender", ctx)).toBe("agent:fina:discord:channel:123456");
+    });
+
+    it("does not rewrite discord:channel: keys when sender does not match", () => {
+      const ctx = makeCtx({
+        SessionKey: "agent:fina:discord:channel:123456",
+        ChatType: "direct",
+        From: "discord:789",
+        SenderId: "789",
+      });
+      expect(resolveSessionKey("per-sender", ctx)).toBe("agent:fina:discord:channel:123456");
+    });
+
+    it("handles keys without an agent prefix", () => {
+      const ctx = makeCtx({
+        SessionKey: "discord:channel:123456",
+        ChatType: "direct",
+        From: "discord:123456",
+        SenderId: "123456",
+      });
+      expect(resolveSessionKey("per-sender", ctx)).toBe("discord:direct:123456");
+    });
+  });
+});
diff --git a/src/config/sessions/session-key.ts b/src/config/sessions/session-key.ts
index 3244f5c7c60..70c1eba0a8b 100644
--- a/src/config/sessions/session-key.ts
+++ b/src/config/sessions/session-key.ts
@@ -1,4 +1,5 @@
 import type { MsgContext } from "../../auto-reply/templating.js";
+import { normalizeChatType } from "../../channels/chat-type.js";
 import {
   buildAgentMainSessionKey,
   DEFAULT_AGENT_ID,
@@ -28,7 +29,24 @@ export function deriveSessionKey(scope: SessionScope, ctx: MsgContext) {
 export function resolveSessionKey(scope: SessionScope, ctx: MsgContext, mainKey?: string) {
   const explicit = ctx.SessionKey?.trim();
   if (explicit) {
-    return explicit.toLowerCase();
+    let normalized = explicit.toLowerCase();
+    if (normalizeChatType(ctx.ChatType) === "direct") {
+      normalized = normalized.replace(/^(agent:[^:]+:discord:)dm:/, "$1direct:");
+      const match = normalized.match(/^((?:agent:[^:]+:)?)discord:channel:([^:]+)$/);
+      if (match) {
+        const from = (ctx.From ?? "").trim().toLowerCase();
+        const senderId = (ctx.SenderId ?? "").trim().toLowerCase();
+        const fromDiscordId =
+          from.startsWith("discord:") && !from.includes(":channel:") && !from.includes(":group:")
+            ? from.slice("discord:".length)
+            : "";
+        const directId = senderId || fromDiscordId;
+        if (directId && directId === match[2]) {
+          normalized = `${match[1]}discord:direct:${match[2]}`;
+        }
+      }
+    }
+    return normalized;
   }
   const raw = deriveSessionKey(scope, ctx);
   if (scope === "global") {