diff --git a/extensions/msteams/src/polls.ts b/extensions/msteams/src/polls.ts
index 98a468226d3..feeb41c9d6e 100644
--- a/extensions/msteams/src/polls.ts
+++ b/extensions/msteams/src/polls.ts
@@ -1,5 +1,4 @@
 import crypto from "node:crypto";
-import { isRecord, readNestedString } from "./attachments/shared.js";
 import { resolveMSTeamsStorePath } from "./storage.js";
 import { readJsonFile, withFileLock, writeJsonFile } from "./store-fs.js";
 
@@ -48,6 +47,18 @@ const STORE_FILENAME = "msteams-polls.json";
 const MAX_POLLS = 1000;
 const POLL_TTL_MS = 30 * 24 * 60 * 60 * 1000;
 
+function isRecord(value: unknown): value is Record<string, unknown> {
+  return typeof value === "object" && value !== null && !Array.isArray(value);
+}
+
+function normalizeOptionalString(value: unknown): string | undefined {
+  if (typeof value !== "string") {
+    return undefined;
+  }
+  const trimmed = value.trim();
+  return trimmed ? trimmed : undefined;
+}
+
 function normalizeChoiceValue(value: unknown): string | null {
   if (typeof value === "string") {
     const trimmed = value.trim();
@@ -87,6 +98,10 @@ function readNestedValue(value: unknown, keys: Array<string | number>): unknown
   return current;
 }
 
+function readNestedString(value: unknown, keys: Array<string | number>): string | undefined {
+  return normalizeOptionalString(readNestedValue(value, keys));
+}
+
 export function extractMSTeamsPollVote(
   activity: { value?: unknown } | undefined,
 ): MSTeamsPollVote | null {
diff --git a/extensions/msteams/src/store-fs.ts b/extensions/msteams/src/store-fs.ts
index 1eb592ae960..d2d6767da59 100644
--- a/extensions/msteams/src/store-fs.ts
+++ b/extensions/msteams/src/store-fs.ts
@@ -1,9 +1,6 @@
 import fs from "node:fs";
-import {
-  readJsonFileWithFallback,
-  withFileLock as withPathLock,
-  writeJsonFileAtomically,
-} from "../runtime-api.js";
+import { withFileLock as withPathLock } from "openclaw/plugin-sdk/file-lock";
+import { readJsonFileWithFallback, writeJsonFileAtomically } from "openclaw/plugin-sdk/json-store";
 
 const STORE_LOCK_OPTIONS = {
   retries: {