diff --git a/src/routes/register/+layout.svelte b/src/routes/register/+layout.svelte
index 5884975..25b6ba1 100644
--- a/src/routes/register/+layout.svelte
+++ b/src/routes/register/+layout.svelte
@@ -1,3 +1,3 @@
-<div class="flex justify-center w-full bg-base-200">
+<div class="flex justify-center w-full min-h-full bg-base-200">
 	<slot />
 </div>
diff --git a/src/routes/register/+page.svelte b/src/routes/register/+page.svelte
index 8717ea3..930e997 100644
--- a/src/routes/register/+page.svelte
+++ b/src/routes/register/+page.svelte
@@ -12,7 +12,7 @@
 
 <!--the tooltip when not all fields are correctly filled won't completely show if the overflow is hidden-->
 <div
-	class="grid card w-11/12 xl:w-2/3 2xl:w-1/2 p-6 my-12 bg-base-100 shadow-lg"
+	class="grid card w-11/12 xl:w-2/3 2xl:w-1/2 p-6 my-12 bg-base-100 shadow-lg h-min"
 	class:overflow-hidden={registered}
 >
 	{#if !registered}
diff --git a/src/routes/register/+server.ts b/src/routes/register/+server.ts
index 4efd4ca..c1c34fe 100644
--- a/src/routes/register/+server.ts
+++ b/src/routes/register/+server.ts
@@ -9,6 +9,23 @@ import { User } from '$lib/server/database';
 
 export const POST = (async ({ request }) => {
 	const data = await request.formData();
+	const firstname = data.get('firstname') as string | null;
+	const lastname = data.get('lastname') as string | null;
+	const birthday: number = Date.parse(data.get('birthday') as string);
+	const telephone = data.get('telephone') as string | null;
+	const username = data.get('username') as string | null;
+	const playertype = data.get('playertype') as string | null;
+	const password = data.get('password') as string | null;
+
+	if (
+		firstname == null ||
+		lastname == null ||
+		Number.isNaN(birthday) ||
+		username == null ||
+		playertype == null
+	) {
+		throw error(400, 'Ungültige Parameter');
+	}
 
 	let uuid: string;
 	try {
@@ -31,17 +48,34 @@ export const POST = (async ({ request }) => {
 			throw error(400, e.message);
 		}
 		console.error((e as Error).message);
-		return new Response();
+		throw error(500);
+	}
+
+	if (await User.findOne({ where: { uuid: uuid } })) {
+		throw error(400, 'Dieser Spieler wurde bereits registriert');
+	} else if (
+		await User.findOne({
+			where: {
+				firstname: firstname,
+				lastname: lastname,
+				birthday: new Date(birthday).toUTCString()
+			}
+		})
+	) {
+		throw error(
+			400,
+			'Du hast dich bereits angemeldet. Sollte dies nicht der Fall sein, wende dich bitte an einen Administrator'
+		);
 	}
 
 	await User.create({
-		firstname: data.get('firstname'),
-		lastname: data.get('lastname'),
-		birthday: data.get('birthday'),
-		telephone: data.get('telephone'),
-		username: data.get('username'),
-		playertype: data.get('playertype'),
-		password: data.get('password'),
+		firstname: firstname,
+		lastname: lastname,
+		birthday: new Date(birthday).toUTCString(),
+		telephone: telephone,
+		username: username,
+		playertype: playertype,
+		password: password,
 		uuid: uuid
 	});
 
diff --git a/src/routes/register/Register.svelte b/src/routes/register/Register.svelte
index 28519bf..8866d68 100644
--- a/src/routes/register/Register.svelte
+++ b/src/routes/register/Register.svelte
@@ -209,7 +209,7 @@
 					>
 						<form method="dialog" class="modal-box">
 							<button class="btn btn-sm btn-circle btn-ghost absolute right-2 top-2">✕</button>
-							<h3 class="font-bold text-lg">Error</h3>
+							<h3 class="font-bold text-lg">Fehler</h3>
 							<p class="py-4">{error.message}</p>
 						</form>
 						<form method="dialog" class="modal-backdrop bg-[rgba(0,0,0,.2)]">
diff --git a/src/routes/register/RegistrationComplete.svelte b/src/routes/register/RegistrationComplete.svelte
index 0840b18..bf08226 100644
--- a/src/routes/register/RegistrationComplete.svelte
+++ b/src/routes/register/RegistrationComplete.svelte
@@ -1,5 +1,5 @@
 <script lang="ts">
-	import { ChevronRight } from 'svelte-heros-v2';
+	import { ChevronLeft } from 'svelte-heros-v2';
 	import { createEventDispatcher } from 'svelte';
 	import { env } from '$env/dynamic/public';
 
@@ -18,7 +18,7 @@
 
 <div class="flex items-center h-12 mb-2">
 	<button class="sm:absolute btn btn-sm btn-square" on:click={() => dispatch('close')}>
-		<ChevronRight variation="outline" />
+		<ChevronLeft variation="outline" />
 	</button>
 	<h1 class="text-center text-xl sm:text-3xl m-auto">Registrierung erfolgreich</h1>
 </div>