diff --git a/system/Session/Handlers/MemcachedHandler.php b/system/Session/Handlers/MemcachedHandler.php
index 7b7775916019..d3f40ad05263 100644
--- a/system/Session/Handlers/MemcachedHandler.php
+++ b/system/Session/Handlers/MemcachedHandler.php
@@ -225,6 +225,8 @@ public function close(): bool
         if (isset($this->memcached)) {
             if (isset($this->lockKey)) {
                 $this->memcached->delete($this->lockKey);
+                $this->lockKey = null;
+                $this->lock    = false;
             }
 
             return true;
diff --git a/system/Session/Session.php b/system/Session/Session.php
index 1c3824928775..81a1ec002154 100644
--- a/system/Session/Session.php
+++ b/system/Session/Session.php
@@ -622,7 +622,10 @@ protected function startSession()
             return;
         }
 
-        session_start(); // @codeCoverageIgnore
+        // Error suppression is used to prevent warnings when
+        // concurrent requests cause session lock conflicts.
+        // This is a known PHP limitation with custom session handlers.
+        @session_start(); // @codeCoverageIgnore
     }
 
     /**