diff --git a/src/hooks/useGitHubData.ts b/src/hooks/useGitHubData.ts
index f4c78cf6..7dfb947b 100644
--- a/src/hooks/useGitHubData.ts
+++ b/src/hooks/useGitHubData.ts
@@ -1,4 +1,4 @@
-import { useState, useCallback, useRef } from 'react';
+import { useState, useCallback, useRef, useEffect } from 'react';
 import { Octokit } from '@octokit/core';
 
 interface GitHubItem {
@@ -34,6 +34,7 @@ export const useGitHubData = (
 
   // Prevent stale responses overwriting latest data
   const lastRequestId = useRef(0);
+  const abortControllerRef = useRef<AbortController | null>(null);
 
   const fetchPaginated = async (
     octokit: Octokit,
@@ -41,7 +42,8 @@ export const useGitHubData = (
     type: 'issue' | 'pr',
     page = 1,
     perPage = 10,
-    filters: FetchFilters = {}
+    filters: FetchFilters = {},
+    signal?: AbortSignal
   ) => {
     let q = `author:${username} is:${type}`;
 
@@ -77,6 +79,9 @@ export const useGitHubData = (
         order: 'desc',
         per_page: perPage,
         page,
+        request: {
+          signal,
+        },
       }
     );
 
@@ -100,6 +105,14 @@ export const useGitHubData = (
         return;
       }
 
+      // Cancel any active in-flight request before triggering a new one
+      if (abortControllerRef.current) {
+        abortControllerRef.current.abort();
+      }
+
+      const controller = new AbortController();
+      abortControllerRef.current = controller;
+
       const requestId = ++lastRequestId.current;
 
       setLoading(true);
@@ -122,7 +135,8 @@ export const useGitHubData = (
               'issue',
               page,
               perPage,
-              filters
+              filters,
+              controller.signal
             )
           );
         }
@@ -135,15 +149,16 @@ export const useGitHubData = (
               'pr',
               page,
               perPage,
-              filters
+              filters,
+              controller.signal
             )
           );
         }
 
         const results = await Promise.allSettled(requests);
 
-        // Ignore stale requests
-        if (requestId !== lastRequestId.current) {
+        // Ignore stale or aborted requests
+        if (requestId !== lastRequestId.current || abortControllerRef.current !== controller) {
           return;
         }
 
@@ -156,6 +171,10 @@ export const useGitHubData = (
             setIssues(issueResult.value.items);
             setTotalIssues(issueResult.value.total);
           } else {
+            const reason = issueResult.reason;
+            if (reason && reason.name === 'AbortError') {
+              return;
+            }
             setIssues([]);
             setTotalIssues(0);
           }
@@ -170,6 +189,10 @@ export const useGitHubData = (
             setPrs(prResult.value.items);
             setTotalPrs(prResult.value.total);
           } else {
+            const reason = prResult.reason;
+            if (reason && reason.name === 'AbortError') {
+              return;
+            }
             setPrs([]);
             setTotalPrs(0);
           }
@@ -180,6 +203,12 @@ export const useGitHubData = (
         );
 
         if (hasRejected) {
+          const wasAborted = results.some(
+            (result) => result.status === 'rejected' && result.reason?.name === 'AbortError'
+          );
+          if (wasAborted) {
+            return;
+          }
           setError(
             'Some GitHub data could not be fetched completely.'
           );
@@ -187,15 +216,20 @@ export const useGitHubData = (
 
         setRateLimited(false);
       } catch (err: unknown) {
-        if (requestId !== lastRequestId.current) {
+        if (requestId !== lastRequestId.current || abortControllerRef.current !== controller) {
           return;
         }
 
         const error = err as {
           status?: number;
           message?: string;
+          name?: string;
         };
 
+        if (error.name === 'AbortError') {
+          return;
+        }
+
         const errorMessage =
           error.message?.toLowerCase() || '';
 
@@ -231,7 +265,7 @@ export const useGitHubData = (
           );
         }
       } finally {
-        if (requestId === lastRequestId.current) {
+        if (requestId === lastRequestId.current && abortControllerRef.current === controller) {
           setLoading(false);
         }
       }
@@ -239,6 +273,15 @@ export const useGitHubData = (
     [getOctokit, rateLimited]
   );
 
+  // Cleanup abort controller on component unmount
+  useEffect(() => {
+    return () => {
+      if (abortControllerRef.current) {
+        abortControllerRef.current.abort();
+      }
+    };
+  }, []);
+
   return {
     issues,
     prs,
diff --git a/src/pages/Tracker/Tracker.tsx b/src/pages/Tracker/Tracker.tsx
index 82143050..04df12d7 100644
--- a/src/pages/Tracker/Tracker.tsx
+++ b/src/pages/Tracker/Tracker.tsx
@@ -81,29 +81,35 @@ const Home: React.FC = () => {
   const [startDate, setStartDate] = useState("");
   const [endDate, setEndDate] = useState("");
 
-  // Prefill from user context on mount
-  useEffect(() => {
-    const user = userContext?.user;
-    if (user?.username) setUsername(user.username);
-    if (user?.token) setToken(user.token);
-  }, []);
-
-  const debouncedUsername = useDebounce(username, 800);
+  const [debouncedUsername, setDebouncedUsername] = useState(username);
 
-  // Auto-fetch when debounced username or token changes
   useEffect(() => {
-    if (debouncedUsername) {
-      setPage(0);
-      fetchData(debouncedUsername, 1, ROWS_PER_PAGE);
+    if (!username) {
+      setDebouncedUsername("");
+      return;
     }
-  }, [debouncedUsername, token]);
+    const handler = setTimeout(() => {
+      setDebouncedUsername(username);
+    }, 500);
+
+    return () => {
+      clearTimeout(handler);
+    };
+  }, [username]);
 
-  // Fetch when tab or page changes (username already set)
+  // Fetch data when debouncedUsername, tab, or page changes
   useEffect(() => {
-    if (username) {
-      fetchData(username, page + 1, ROWS_PER_PAGE);
+    if (debouncedUsername && debouncedUsername.trim().length >= 1) {
+      fetchData(debouncedUsername, page + 1, ROWS_PER_PAGE);
     }
-  }, [tab, page]);
+  }, [debouncedUsername, tab, page]);
+
+  const handleSubmit = (e: React.FormEvent<HTMLFormElement>): void => {
+    e.preventDefault();
+    setPage(0);
+    setDebouncedUsername(username);
+    fetchData(username, 1, ROWS_PER_PAGE);
+  };
 
   const handlePageChange = (_: unknown, newPage: number) => {