login fixes

@@ -483,8 +483,8 @@ public enum Endpoint {
         case .refreshToken, .logout:
             return .authentication
             
-        // Partner Cosmote - /partners/cosmote/verify, /partners/oauth/{appUUID}/token
-        case .verifyTicket, .getCosmoteUser:
+        // Partner Cosmote - /partners/cosmote/verify, /partners/oauth/{appUUID}/token, /partners/dei/app_login
+        case .verifyTicket, .getCosmoteUser, .deiLogin:
             return .partnerCosmote
             
         // Session - /api/session/{sessionUuid}

@@ -997,7 +997,7 @@ extension NetworkService {
         // Create TokenModel and store in database
         let tokenModel = TokenModel(
             accessToken: accessToken,
-            refreshToken: refreshToken, // May be nil/null initially
+            refreshToken: refreshToken ?? "", // Provide empty string if nil (future-ready for when refresh tokens become available)
             clientId: tokens["client_id"] as? String,
             clientSecret: tokens["client_secret"] as? String
         )