diff --git a/memory_system.py b/memory_system.py
index b5666d1..01b9684 100644
--- a/memory_system.py
+++ b/memory_system.py
@@ -1,10 +1,10 @@
 """
 title: Memory System
 description: A semantic memory management system for Open WebUI that consolidates, deduplicates, and retrieves personalized user memories using LLM operations.
-version: 1.2.0
+version: 1.2.1
 authors: https://github.com/mtayfur
 license: Apache-2.0
-required_open_webui_version: 0.6.37
+required_open_webui_version: 0.6.40
 """
 
 import asyncio
@@ -1249,14 +1249,10 @@ class Filter:
     def _extract_text_from_content(self, content) -> str:
         if isinstance(content, str):
             return content
-        elif isinstance(content, list):
-            text_parts = []
-            for item in content:
-                if isinstance(item, dict) and item.get("type") == "text":
-                    text_parts.append(item.get("text", ""))
-            return " ".join(text_parts)
-        elif isinstance(content, dict) and "text" in content:
-            return content["text"]
+        if isinstance(content, list):
+            return " ".join(item.get("text", "") for item in content if isinstance(item, dict) and item.get("type") == "text")
+        if isinstance(content, dict) and "text" in content:
+            return content.get("text", "")
         return ""
 
     def _validate_system_configuration(self) -> None:
@@ -1279,7 +1275,7 @@ class Filter:
 
     def _compute_text_hash(self, text: str) -> str:
         """Compute SHA256 hash for text caching."""
-        return hashlib.sha256(text.encode()).hexdigest()
+        return hashlib.sha256(str(text).encode()).hexdigest()
 
     async def _detect_embedding_dimension(self) -> None:
         """Detect embedding dimension by generating a test embedding."""
@@ -1400,10 +1396,11 @@ class Filter:
         if timeout is None:
             timeout = Constants.DATABASE_OPERATION_TIMEOUT_SEC
         
-        return await asyncio.wait_for(
+        memories = await asyncio.wait_for(
             asyncio.to_thread(Memories.get_memories_by_user_id, user_id),
             timeout=timeout,
         )
+        return [m for m in (memories or []) if m.content]
 
     def _log_retrieved_memories(self, memories: List[Dict[str, Any]], context_type: str = "semantic") -> None:
         """Log retrieved memories with concise formatting showing key statistics and semantic values."""
@@ -1434,7 +1431,7 @@ class Filter:
     def _cache_key(self, cache_type: str, user_id: str, content: Optional[str] = None) -> str:
         """Unified cache key generation for all cache types."""
         if content:
-            content_hash = hashlib.sha256(content.encode("utf-8")).hexdigest()[: Constants.CACHE_KEY_HASH_PREFIX_LENGTH]
+            content_hash = hashlib.sha256(str(content).encode("utf-8")).hexdigest()[: Constants.CACHE_KEY_HASH_PREFIX_LENGTH]
             return f"{cache_type}_{user_id}:{content_hash}"
         return f"{cache_type}_{user_id}"
 
@@ -1637,7 +1634,7 @@ class Filter:
 
         user_message, should_skip, skip_reason = await self._process_user_message(body)
 
-        skip_cache_key = self._cache_key(self._cache_manager.SKIP_STATE_CACHE, user_id, user_message or "")
+        skip_cache_key = self._cache_key(self._cache_manager.SKIP_STATE_CACHE, user_id, user_message)
         await self._cache_manager.put(
             user_id,
             self._cache_manager.SKIP_STATE_CACHE,
@@ -1771,7 +1768,7 @@ class Filter:
                 user_memories,
             )
 
-            memory_contents = [memory.content for memory in user_memories if memory.content and len(memory.content.strip()) >= Constants.MIN_MESSAGE_CHARS]
+            memory_contents = [memory.content for memory in user_memories if len(memory.content.strip()) >= Constants.MIN_MESSAGE_CHARS]
 
             if memory_contents:
                 await self._generate_embeddings(memory_contents, user_id)