diff --git a/app/Controllers/API_Tubes.php b/app/Controllers/API_Tubes.php
index e1b3b63..af140b1 100644
--- a/app/Controllers/API_Tubes.php
+++ b/app/Controllers/API_Tubes.php
@@ -27,7 +27,7 @@ class API_Tubes extends BaseController {
 	
 	public function unreceive($access, $sample) {
 		$db = \Config\Database::connect();
-		$sql = "UPDATE SP_TUBES set TUBESTATUS=null where SP_ACCESSNUMBER='$access' and SAMPLETYPE='$sample'";
+		$sql = "UPDATE SP_TUBES set TUBESTATUS=0 where SP_ACCESSNUMBER='$access' and SAMPLETYPE='$sample'";
 		$query = $db->query($sql);
     }
 	
@@ -58,7 +58,7 @@ class API_Tubes extends BaseController {
 	
 	public function unreceiveAll($access) {
 		$db = \Config\Database::connect();
-		$sql = "UPDATE SP_TUBES set TUBESTATUS=null where SP_ACCESSNUMBER='$access'";
+		$sql = "UPDATE SP_TUBES set TUBESTATUS=0 where SP_ACCESSNUMBER='$access'";
 		$query = $db->query($sql);
     }