diff --git a/server.py b/server.py
index 9a8d57d..22b4499 100644
--- a/server.py
+++ b/server.py
@@ -204,6 +204,8 @@ def preview_url(
         description="Access token to use for the request."
     ),
 ):
+    if ts:
+        ts = round(ts / 1000)
     if access_token_qs is not None:
         access_token = access_token_qs
     elif access_token_header and access_token_header.startswith("Bearer "):