diff --git a/lib/classes/admission/UserFilterField.class.php b/lib/classes/admission/UserFilterField.class.php
index 72a091785379cdf09a9288c2f458c534889b738f..36ed57cea30e9664e864bb3d8927c42e9fa4161d 100644
--- a/lib/classes/admission/UserFilterField.class.php
+++ b/lib/classes/admission/UserFilterField.class.php
@@ -313,8 +313,13 @@ class UserFilterField
         $parameters = [$userId];
         // Additional requirements given...
         if (is_array($additional)) {
+
+            // Don't use the same database field twice as this can only get ugly.
+            $usedFields = [$this->userDataDbField];
+
             foreach ($additional as $a_condition) {
-                if ($a_condition->id != $this->id && $this->userDataDbTable == $a_condition->userDataDbTable) {
+                if ($a_condition->id != $this->id && $this->userDataDbTable == $a_condition->userDataDbTable &&
+                        !in_array($a_condition->userDataDbField, $usedFields)) {
                     $query .= " AND `" . $a_condition->userDataDbField . "` " . $a_condition->compareOperator . "?";
                     $parameters[] = $a_condition->value;
                 }