diff --git a/ai-hub/app/core/services/preference.py b/ai-hub/app/core/services/preference.py
index 7c4fe55..387663f 100644
--- a/ai-hub/app/core/services/preference.py
+++ b/ai-hub/app/core/services/preference.py
@@ -63,26 +63,24 @@
             return is_success or bool(has_key)
 
         # Build effective combined config for processing
-        def get_effective_providers(section_name, user_section_providers, sys_defaults):
-            # M6/M3: Deep merge system defaults with user overrides.
-            # This ensures that if a user configures a model name in the UI, 
-            # they don't lose the API key from config.yaml if it's not provided in the UI.
-            
-            # Start with system defaults (config.yaml / env)
+        def get_effective_providers(section_name, user_section_providers, sys_defaults, user_section_data):
+            # M6: If the user provides a configuration for a provider that already exists
+            # in the system defaults, we want to "Add" it as a personal account
+            # rather than "Overriding" the system default. This allows both to coexist.
             effective = copy.deepcopy(sys_defaults)
+            user_active = user_section_data.get("active_provider")
             
-            # Layer on overrides (Admin or User)
             if user_section_providers:
                 for p_id, p_data in user_section_providers.items():
-                    if p_id not in effective:
-                        # New provider defined in UI
-                        effective[p_id] = copy.deepcopy(p_data)
-                    else:
-                        # Override existing provider fields
-                        for field, val in p_data.items():
-                            # Only override if the value is meaningful (not empty/null)
-                            if val is not None and val != "" and str(val).lower() != "none":
-                                effective[p_id][field] = val
+                    target_id = p_id
+                    if p_id in effective:
+                        # Collision: Create a distinct personal resource
+                        target_id = f"{p_id}_personal"
+                        # Update the user's active selection to point to their personal version
+                        if user_active == p_id:
+                            user_section_data["active_provider"] = target_id
+                    
+                    effective[target_id] = copy.deepcopy(p_data)
             
             # Filter by health and mask keys for the response
             res = {}
@@ -120,7 +118,7 @@
             return merged
 
         system_llm = get_merged_system_defaults("llm", settings.LLM_PROVIDERS)
-        llm_providers_effective = get_effective_providers("llm", llm_prefs["providers"], system_llm)
+        llm_providers_effective = get_effective_providers("llm", llm_prefs["providers"], system_llm, llm_prefs)
 
         system_tts = get_merged_system_defaults("tts", {
             settings.TTS_PROVIDER: {
@@ -129,12 +127,12 @@
                 "voice": settings.TTS_VOICE_NAME
             }
         })
-        tts_providers_effective = get_effective_providers("tts", tts_prefs["providers"], system_tts)
+        tts_providers_effective = get_effective_providers("tts", tts_prefs["providers"], system_tts, tts_prefs)
 
         system_stt = get_merged_system_defaults("stt", {
             settings.STT_PROVIDER: {"api_key": settings.STT_API_KEY, "model": settings.STT_MODEL_NAME}
         })
-        stt_providers_effective = get_effective_providers("stt", stt_prefs["providers"], system_stt)
+        stt_providers_effective = get_effective_providers("stt", stt_prefs["providers"], system_stt, stt_prefs)
         
         effective = {
             "llm": {