diff --git a/webui.py b/webui.py
index 55a1513..7584f6f 100644
--- a/webui.py
+++ b/webui.py
@@ -407,7 +407,7 @@ async def run_custom_agent(
 
         # Initialize global browser if needed
         #if chrome_cdp not empty string nor None
-        if ((_global_browser is None) or (cdp_url and cdp_url != "" and cdp_url != null)) :
+        if ((_global_browser is None) or (cdp_url and cdp_url != "" and cdp_url != None)) :
             _global_browser = CustomBrowser(
                 config=BrowserConfig(
                     headless=headless,
@@ -418,7 +418,7 @@ async def run_custom_agent(
                 )
             )
 
-        if (_global_browser_context is None  or (chrome_cdp and cdp_url != "" and cdp_url != null)):
+        if (_global_browser_context is None  or (chrome_cdp and cdp_url != "" and cdp_url != None)):
             _global_browser_context = await _global_browser.new_context(
                 config=BrowserContextConfig(
                     trace_path=save_trace_path if save_trace_path else None,