diff --git a/django_seo_js/backends/base.py b/django_seo_js/backends/base.py
index 186a814..8aa2d5f 100644
--- a/django_seo_js/backends/base.py
+++ b/django_seo_js/backends/base.py
@@ -63,7 +63,7 @@ def __init__(self, *args, **kwargs):
     def build_django_response_from_requests_response(self, response):
         r = HttpResponse(response.content)
         for k, v in response.headers.items():
-            if k not in IGNORED_HEADERS:
+            if k.lower() not in IGNORED_HEADERS:
                 r[k] = v
         r['content-length'] = len(response.content)
         r.status_code = response.status_code
diff --git a/django_seo_js/backends/prerender.py b/django_seo_js/backends/prerender.py
index 8d6ec9d..7159cb1 100644
--- a/django_seo_js/backends/prerender.py
+++ b/django_seo_js/backends/prerender.py
@@ -1,5 +1,6 @@
 from django_seo_js import settings
 from base import SEOBackendBase, RequestsBasedBackend
+import json
 
 
 class PrerenderIO(SEOBackendBase, RequestsBasedBackend):
@@ -55,7 +56,7 @@ def update_url(self, url=None, regex=None):
         if regex:
             data["regex"] = regex
 
-        r = self.session.post(self.RECACHE_URL, headers=headers, data=data)
+        r = self.session.post(self.RECACHE_URL, headers=headers, data=json.dumps(data))
         return r.status_code < 500