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apps/Frontend/src/components/settings/insuranceCredTable.tsx

@@ -99,7 +99,7 @@ export function CredentialTable() {
             setModalOpen(true);
           }}
         >
-          <Plus className="mr-2 h-4 w-4" /> Add Credential
+          <Plus className="mr-2 h-4 w-4" /> Add Credentials
         </Button>
       </div>
 

apps/Frontend/src/components/settings/npiProviderTable.tsx

@@ -91,7 +91,7 @@ export function NpiProviderTable() {
             setModalOpen(true);
           }}
         >
-          <Plus className="mr-2 h-4 w-4" /> Add NPI Provider
+          <Plus className="mr-2 h-4 w-4" /> Add NPI Providers
         </Button>
       </div>
 

apps/Frontend/src/components/staffs/staff-table.tsx

@@ -66,7 +66,7 @@ export function StaffTable({
           onClick={onAdd}
           className="px-4 py-2 bg-teal-600 text-white rounded hover:bg-teal-700"
         >
-          Add New Staff
+          Add New Staffs
         </button>
       </div>
 

apps/Frontend/src/pages/settings-page.tsx

@@ -395,7 +395,7 @@ export default function SettingsPage() {
                 addUserMutation.mutate({ username: newUsername.trim(), password: newPassword.trim() });
               }}
             >
-              <h4 className="text-sm font-semibold text-gray-700">Add New User</h4>
+              <h4 className="text-sm font-semibold text-gray-700">Add New Users</h4>
               <div>
                 <label className="block text-sm font-medium">Username</label>
                 <input
@@ -423,7 +423,7 @@ export default function SettingsPage() {
                 className="bg-teal-600 text-white px-4 py-2 rounded hover:bg-teal-700"
                 disabled={addUserMutation.isPending}
               >
-                {addUserMutation.isPending ? "Adding..." : "Add User"}
+                {addUserMutation.isPending ? "Adding..." : "Add"}
               </button>
             </form>
           </CardContent>
@@ -443,7 +443,7 @@ export default function SettingsPage() {
                 formData.get("password")?.toString().trim() || undefined;
 
               updateUserMutate.mutate({
-                username: usernameUser?.trim() || undefined,
+                ...(isAdmin ? {} : { username: usernameUser?.trim() || undefined }),
                 password: password || undefined,
               });
             }}
@@ -455,8 +455,12 @@ export default function SettingsPage() {
                 name="username"
                 value={usernameUser}
                 onChange={(e) => setUsernameUser(e.target.value)}
-                className="mt-1 p-2 border rounded w-full"
+                className="mt-1 p-2 border rounded w-full disabled:bg-gray-100 disabled:cursor-not-allowed disabled:text-gray-500"
+                disabled={isAdmin}
               />
+              {isAdmin && (
+                <p className="text-xs text-gray-500 mt-1">Admin username cannot be changed.</p>
+              )}
             </div>
 
             <div>