diff --git a/chat-core.js b/chat-core.js
index 7155830..a6b5b6c 100644
--- a/chat-core.js
+++ b/chat-core.js
@@ -488,10 +488,20 @@ document.addEventListener("DOMContentLoaded", () => {
             prompt += `\nUser: ${lastUser}`;
         }
 
-        const modelSelectEl = document.getElementById("model-select");
-        const model = modelSelectEl?.value || currentSession.model;
-        if (!model) throw new Error("No model selected");
-        const apiUrl = `https://text.pollinations.ai/${encodeURIComponent(prompt)}?model=${encodeURIComponent(model)}`;
+        const modelSelectEl = document.getElementById("model-select");
+        const model = modelSelectEl?.value || currentSession.model || Storage.getDefaultModel();
+        if (!model) {
+            loadingDiv.textContent = "Error: No model selected.";
+            setTimeout(() => loadingDiv.remove(), 3000);
+            const btn = window._chatInternals?.sendButton || document.getElementById("send-button");
+            const input = window._chatInternals?.chatInput || document.getElementById("chat-input");
+            if (btn) btn.disabled = false;
+            if (input) input.disabled = false;
+            showToast("Please select a model before sending a message.");
+            if (callback) callback();
+            return;
+        }
+        const apiUrl = `https://text.pollinations.ai/${encodeURIComponent(prompt)}?model=${encodeURIComponent(model)}`;
 
         try {
             const res = await window.pollinationsFetch(apiUrl, {
diff --git a/storage.js b/storage.js
index 82befa2..598af0f 100644
--- a/storage.js
+++ b/storage.js
@@ -44,7 +44,12 @@ document.addEventListener("DOMContentLoaded", () => {
   }
 
   function getDefaultModel() {
-    return localStorage.getItem("defaultModelPreference") || "";
+    let model = localStorage.getItem("defaultModelPreference");
+    if (!model) {
+      model = "unity";
+      localStorage.setItem("defaultModelPreference", model);
+    }
+    return model;
   }
 
   function setDefaultModel(modelName) {
diff --git a/ui.js b/ui.js
index 2fd9103..5a3b49c 100644
--- a/ui.js
+++ b/ui.js
@@ -148,41 +148,44 @@ document.addEventListener("DOMContentLoaded", () => {
             });
 
             const currentSession = Storage.getCurrentSession();
-            if (currentSession && currentSession.model) {
-                const modelExists = Array.from(modelSelect.options).some(option => option.value === currentSession.model);
-                if (modelExists) {
-                    modelSelect.value = currentSession.model;
+            const preferredModel = currentSession?.model || Storage.getDefaultModel();
+            if (preferredModel) {
+                const exists = Array.from(modelSelect.options).some(option => option.value === preferredModel);
+                if (exists) {
+                    modelSelect.value = preferredModel;
                 } else {
                     const tempOpt = document.createElement("option");
-                    tempOpt.value = currentSession.model;
-                    tempOpt.textContent = `${currentSession.model} (Previously Selected - May Be Unavailable)`;
+                    tempOpt.value = preferredModel;
+                    tempOpt.textContent = `${preferredModel} (Previously Selected - May Be Unavailable)`;
                     tempOpt.title = "This model may no longer be available";
                     modelSelect.appendChild(tempOpt);
-                    modelSelect.value = currentSession.model;
-                    console.warn(`Model ${currentSession.model} not found in fetched list. Added as unavailable option.`);
+                    modelSelect.value = preferredModel;
+                    console.warn(`Model ${preferredModel} not found in fetched list. Added as unavailable option.`);
                 }
             }
 
             if (!modelSelect.value && modelSelect.options.length > 0) {
-                const firstModel = modelSelect.options[0].value;
+                const unityOption = Array.from(modelSelect.options).find(opt => opt.value === "unity");
+                const firstModel = unityOption ? unityOption.value : modelSelect.options[0].value;
                 modelSelect.value = firstModel;
                 if (currentSession) {
                     Storage.setSessionModel(currentSession.id, firstModel);
                 }
             }
-        } catch (err) {
+        } catch (err) {
             console.error("Failed to fetch text models:", err);
             modelSelect.innerHTML = "";
             const currentSession = Storage.getCurrentSession();
-            if (currentSession && currentSession.model) {
+            const fallbackModel = currentSession?.model || Storage.getDefaultModel();
+            if (fallbackModel) {
                 const sessOpt = document.createElement("option");
-                sessOpt.value = currentSession.model;
-                sessOpt.textContent = `${currentSession.model} (From Session - May Be Unavailable)`;
+                sessOpt.value = fallbackModel;
+                sessOpt.textContent = `${fallbackModel} (From Session - May Be Unavailable)`;
                 modelSelect.appendChild(sessOpt);
-                modelSelect.value = currentSession.model;
+                modelSelect.value = fallbackModel;
             }
-        }
-    }
+        }
+    }
     fetchPollinationsModels();
     newSessionBtn.addEventListener("click", () => {
         const newSess = Storage.createSession("New Chat");