diff --git a/backend/open_webui/routers/ollama.py b/backend/open_webui/routers/ollama.py
index 23a43aaaa9..b283db9ae8 100644
--- a/backend/open_webui/routers/ollama.py
+++ b/backend/open_webui/routers/ollama.py
@@ -55,14 +55,15 @@ log = logging.getLogger(__name__)
 # response body.  Forwarding them verbatim causes desktop / programmatic
 # clients to attempt decompression of an already-decoded payload, resulting
 # in ZlibError.  See https://github.com/aio-libs/aiohttp/issues/4462.
-_STRIP_PROXY_HEADERS = frozenset({'Content-Encoding', 'Content-Length', 'Transfer-Encoding'})
+# Also drop server and date: uvicorn adds its own and forwarding both duplicates them.
+_STRIP_PROXY_HEADERS = frozenset({'content-encoding', 'content-length', 'transfer-encoding', 'server', 'date'})
 _MODEL_LIST_TIMEOUT = aiohttp.ClientTimeout(total=AIOHTTP_CLIENT_TIMEOUT_MODEL_LIST)
 BASE_MODELS_CACHE_KEY = f'{REDIS_KEY_PREFIX}:models:base'
 
 
 def _clean_proxy_headers(raw_headers) -> dict:
-    """Return a copy of *raw_headers* with stale encoding headers removed."""
-    return {k: v for k, v in raw_headers.items() if k not in _STRIP_PROXY_HEADERS}
+    """Return a copy of *raw_headers* without the encoding, server and date headers."""
+    return {k: v for k, v in raw_headers.items() if k.lower() not in _STRIP_PROXY_HEADERS}
 
 
 async def send_get_request(
diff --git a/backend/open_webui/routers/openai.py b/backend/open_webui/routers/openai.py
index c62b2f7194..8c8f96183e 100644
--- a/backend/open_webui/routers/openai.py
+++ b/backend/open_webui/routers/openai.py
@@ -74,15 +74,16 @@ log = logging.getLogger(__name__)
 # response body.  Forwarding them verbatim causes desktop / programmatic
 # clients to attempt decompression of an already-decoded payload, resulting
 # in ZlibError.  See https://github.com/aio-libs/aiohttp/issues/4462.
-_STRIP_PROXY_HEADERS = frozenset({'Content-Encoding', 'Content-Length', 'Transfer-Encoding'})
+# Also drop server and date: uvicorn adds its own and forwarding both duplicates them.
+_STRIP_PROXY_HEADERS = frozenset({'content-encoding', 'content-length', 'transfer-encoding', 'server', 'date'})
 _MODEL_LIST_TIMEOUT = aiohttp.ClientTimeout(total=AIOHTTP_CLIENT_TIMEOUT_MODEL_LIST)
 _UNSUPPORTED_OPENAI_MODEL_KEYWORDS = ('babbage', 'dall-e', 'davinci', 'embedding', 'tts', 'whisper')
 BASE_MODELS_CACHE_KEY = f'{REDIS_KEY_PREFIX}:models:base'
 
 
 def _clean_proxy_headers(raw_headers) -> dict:
-    """Return a copy of *raw_headers* with stale encoding headers removed."""
-    return {k: v for k, v in raw_headers.items() if k not in _STRIP_PROXY_HEADERS}
+    """Return a copy of *raw_headers* without the encoding, server and date headers."""
+    return {k: v for k, v in raw_headers.items() if k.lower() not in _STRIP_PROXY_HEADERS}
 
 
 async def send_get_request(