diff --git a/web/register.php b/web/register.php
index a757365..d0600e8 100644
--- a/web/register.php
+++ b/web/register.php
@@ -15,10 +15,15 @@ $user_key = generateRandomAuthKey();
 
 $pdo = getDatabase();
 
+$pdo->beginTransaction();
+
 if ($ispro)
 {
-	if (!verifyOrderToken($pro_token)) die(json_encode(['success' => false, 'message' => 'Purchase token could not be verified']));
-
+	if (!verifyOrderToken($pro_token))
+	{
+		$pdo->rollBack();
+		die(json_encode(['success' => false, 'message' => 'Purchase token could not be verified']));
+	}
 
 	$stmt = $pdo->prepare('UPDATE users SET is_pro=0, pro_token=NULL WHERE user_id <> :uid AND pro_token = :ptk');
 	$stmt->execute(['uid' => $user_id, 'ptk' => $pro_token]);
@@ -28,6 +33,11 @@ $stmt = $pdo->prepare('INSERT INTO users (user_key, fcm_token, is_pro, pro_token
 $stmt->execute(['key' => $user_key, 'token' => $fcmtoken, 'bpro' => $ispro, 'spro' => $ispro ? $pro_token : null]);
 $user_id = $pdo->lastInsertId('user_id');
 
+$stmt = $pdo->prepare('UPDATE users SET fcm_token=NULL WHERE user_id <> :uid AND fcm_token=:ft');
+$stmt->execute(['uid' => $user_id, 'ft' => $fcm_token]);
+
+$pdo->commit();
+
 echo json_encode(
 [
 	'success'   => true,