diff --git a/webapp/models/Market.php b/webapp/models/Market.php
index 0ffdc533..cbd49c29 100644
--- a/webapp/models/Market.php
+++ b/webapp/models/Market.php
@@ -34,7 +34,7 @@ class Market extends BaseModel {
                 'seller' => $seller,
                 'nft_token' => $nftToken,
                 'amount' => $amount,
-                'currency' => $currency,
+                'currency' => strtolower($currency),
                 'price' => $price,
                 'activated' => 1,
                 'selltime' => myself()->_getNowTime(),