diff --git a/htdocs/core/class/commonobject.class.php b/htdocs/core/class/commonobject.class.php
index 3758c0c3d6c..b8b04f032aa 100644
--- a/htdocs/core/class/commonobject.class.php
+++ b/htdocs/core/class/commonobject.class.php
@@ -4558,10 +4558,11 @@ abstract class CommonObject
 			$deletetarget = true;
 		}
 
+		$element = $this->getElementType();
 		$sourceid = (!empty($sourceid) ? $sourceid : $this->id);
-		$sourcetype = (!empty($sourcetype) ? $sourcetype : $this->element);
+		$sourcetype = (!empty($sourcetype) ? $sourcetype : $element);
 		$targetid = (!empty($targetid) ? $targetid : $this->id);
-		$targettype = (!empty($targettype) ? $targettype : $this->element);
+		$targettype = (!empty($targettype) ? $targettype : $element);
 		$this->db->begin();
 		$error = 0;
 
@@ -4587,14 +4588,14 @@ abstract class CommonObject
 			} else {
 				if ($deletesource) {
 					$sql .= " fk_source = " . ((int) $sourceid) . " AND sourcetype = '" . $this->db->escape($sourcetype) . "'";
-					$sql .= " AND fk_target = " . ((int) $this->id) . " AND targettype = '" . $this->db->escape($this->element) . "'";
+					$sql .= " AND fk_target = " . ((int) $this->id) . " AND targettype = '" . $this->db->escape($element) . "'";
 				} elseif ($deletetarget) {
 					$sql .= " fk_target = " . ((int) $targetid) . " AND targettype = '" . $this->db->escape($targettype) . "'";
-					$sql .= " AND fk_source = " . ((int) $this->id) . " AND sourcetype = '" . $this->db->escape($this->element) . "'";
+					$sql .= " AND fk_source = " . ((int) $this->id) . " AND sourcetype = '" . $this->db->escape($element) . "'";
 				} else {
-					$sql .= " (fk_source = " . ((int) $this->id) . " AND sourcetype = '" . $this->db->escape($this->element) . "')";
+					$sql .= " (fk_source = " . ((int) $this->id) . " AND sourcetype = '" . $this->db->escape($element) . "')";
 					$sql .= " OR";
-					$sql .= " (fk_target = " . ((int) $this->id) . " AND targettype = '" . $this->db->escape($this->element) . "')";
+					$sql .= " (fk_target = " . ((int) $this->id) . " AND targettype = '" . $this->db->escape($element) . "')";
 				}
 			}