diff --git a/src/app/(protected)/workorders/_components/view/work-order-activity-panel.tsx b/src/app/(protected)/workorders/_components/view/work-order-activity-panel.tsx
index 61d3d060..ca276156 100644
--- a/src/app/(protected)/workorders/_components/view/work-order-activity-panel.tsx
+++ b/src/app/(protected)/workorders/_components/view/work-order-activity-panel.tsx
@@ -75,9 +75,14 @@ export function WorkOrderActivityPanel({
             if (!trimmed) {
               return;
             }
-            void Promise.resolve(onSubmitComment(trimmed)).then(() => {
-              setCommentText("");
-            });
+            void (async () => {
+              try {
+                await onSubmitComment(trimmed);
+                setCommentText("");
+              } catch {
+                // Mutation toast handles failure; keep the draft for retry.
+              }
+            })();
           }}
           className="mt-4 flex flex-col gap-2"
         >
diff --git a/src/domain/work-orders/utils/comment-mentions.ts b/src/domain/work-orders/utils/comment-mentions.ts
index 21302f1a..b3542bcd 100644
--- a/src/domain/work-orders/utils/comment-mentions.ts
+++ b/src/domain/work-orders/utils/comment-mentions.ts
@@ -80,7 +80,8 @@ function appendPlainMentionMatches(
 
   const sortedNames = [...mentionNames].sort((a, b) => b.length - a.length);
   const namePattern = sortedNames.map((name) => escapeRegExp(name)).join("|");
-  const mentionRegex = new RegExp(`@(${namePattern})`, "g");
+  // Require a non-word boundary after the name so "@Ann" does not match inside "@Annual".
+  const mentionRegex = new RegExp(`@(${namePattern})(?![\\w])`, "g");
 
   let cursor = 0;
   for (const match of plainText.matchAll(mentionRegex)) {
diff --git a/src/test/domain/work-orders/utils/comment-mentions.test.ts b/src/test/domain/work-orders/utils/comment-mentions.test.ts
index c1f9dd3d..95e03ebc 100644
--- a/src/test/domain/work-orders/utils/comment-mentions.test.ts
+++ b/src/test/domain/work-orders/utils/comment-mentions.test.ts
@@ -70,6 +70,17 @@ describe("comment-mentions", () => {
     ]);
   });
 
+  it("does not highlight shorter mention names as prefixes of longer @words", () => {
+    const text = "Check @Annual maintenance with @Ann";
+
+    expect(buildCommentBodySegments(text, ["user-ann"], [{ id: "user-ann", name: "Ann" }])).toEqual(
+      [
+        { type: "text", value: "Check @Annual maintenance with " },
+        { type: "mention", userId: "Ann", label: "Ann" },
+      ],
+    );
+  });
+
   it("finds active mention query at cursor", () => {
     const text = "Hello @ja";
     const query = findActiveMentionQuery(text, text.length);