diff --git a/src/app/api/rest/v1/isUsername/route.ts b/src/app/api/rest/v1/isUsername/route.ts
index 1be0ff4..6e60734 100644
--- a/src/app/api/rest/v1/isUsername/route.ts
+++ b/src/app/api/rest/v1/isUsername/route.ts
@@ -1,29 +1,25 @@
 import {NextRequest, NextResponse} from "next/server";
+import { createClient } from "@/utils/supabase/server";
 
 export async function POST(req: NextRequest): Promise<NextResponse> {
-  let response = NextResponse.next({
-    request: {
-      headers: req.headers,
-    },
-  })
+  try {
+    const supabase = createClient();
+    const body = await req.json();
+    if (!body.username) {
+      return NextResponse.json({ error: 'username is required' }, { status: 400 });
+    }
 
-  const body = await req.json()
+    const { data, error } = await supabase
+      .rpc('is_username_exist',
+        { username: body.username }
+      );
 
-  if ( !body.username ) {
-    return NextResponse.json({ error: 'username is required' })
-  }
+    if (error) {
+      return NextResponse.json({ error: error.message }, { status: 500 });
+    }
 
-  let res = await fetch(`${process.env.NEXT_PUBLIC_SUPABASE_URL}/rest/v1/rpc/is_username_exist`, {
-    method: 'POST',
-    headers: {
-      "apikey": process.env.NEXT_PUBLIC_SUPABASE_ANON_KEY!,
-      "Authorization": `Bearer ${process.env.NEXT_PUBLIC_SUPABASE_ANON_KEY!}`,
-      "Content-Type": "application/json",
-    },
-    body: JSON.stringify(body)
-  });
-  
-  let data = await res.json();
-  
-  return NextResponse.json({ state: data });
+    return NextResponse.json({ state: data }, { status: 200 });
+  } catch (error: any) {
+    return NextResponse.json({ error: error.message }, { status: 500 });
+  }
 }
\ No newline at end of file