fixed build error

pages/subscribe.tsx

@@ -1,6 +1,6 @@
 import SubmitButton from "@/components/SubmitButton";
 import { signOut } from "next-auth/react";
-import { useEffect, useState } from "react";
+import { useState } from "react";
 import { toast } from "react-hot-toast";
 import { useSession } from "next-auth/react";
 import { useRouter } from "next/router";