diff --git a/src/Core/DB/DB.php b/src/Core/DB/DB.php
index b2586a1225..3cd523a5d8 100644
--- a/src/Core/DB/DB.php
+++ b/src/Core/DB/DB.php
@@ -32,6 +32,7 @@
 
 namespace App\Core\DB;
 
+use App\Util\Exception\DuplicateFoundException;
 use App\Util\Exception\NotFoundException;
 use App\Util\Formatting;
 use Doctrine\Common\Collections\Criteria;
@@ -163,7 +164,11 @@ abstract class DB
         if (count($res) == 1) {
             return $res[0];
         } else {
-            throw new NotFoundException("No value in table {$table} matches the requested criteria");
+            if (count($res) == 0) {
+                throw new NotFoundException("No value in table {$table} matches the requested criteria");
+            } else {
+                throw new DuplicateFoundException("Multiple values in table {$table} match the requested criteria");
+            }
         }
     }
 
diff --git a/src/Util/Exception/DuplicateFoundException.php b/src/Util/Exception/DuplicateFoundException.php
new file mode 100644
index 0000000000..5dda046991
--- /dev/null
+++ b/src/Util/Exception/DuplicateFoundException.php
@@ -0,0 +1,39 @@
+<?php
+
+// {{{ License
+// This file is part of GNU social - https://www.gnu.org/software/social
+//
+// GNU social is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Affero General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// GNU social is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU Affero General Public License for more details.
+//
+// You should have received a copy of the GNU Affero General Public License
+// along with GNU social.  If not, see <http://www.gnu.org/licenses/>.
+// }}}
+
+/**
+ * Duplicate value found in DB when not expected
+ *
+ * @category  Exception
+ * @package   GNUsocial
+ *
+ * @author    Hugo Sales <hugo@hsal.es>
+ * @copyright 2021 Free Software Foundation, Inc http://www.fsf.org
+ * @license   https://www.gnu.org/licenses/agpl.html GNU AGPL v3 or later
+ */
+
+namespace App\Util\Exception;
+
+class DuplicateFoundException extends ServerException
+{
+    public function __construct(string $m)
+    {
+        parent::__construct($m);
+    }
+}