Index: backend/src/main/java/com/tradingmk/backend/controller/PortfolioController.java
===================================================================
--- backend/src/main/java/com/tradingmk/backend/controller/PortfolioController.java	(revision d12f01b171edcf326297341c70d7ad611ac288ee)
+++ backend/src/main/java/com/tradingmk/backend/controller/PortfolioController.java	(revision 008dcb86144595548e0692fb8ce6e571e23f86b9)
@@ -54,5 +54,5 @@
         PortfolioDTO portfolioDTO = new PortfolioDTO(portfolio.getBalance(), holdings);
 
-        return ResponseEntity.ok(portfolio);
+        return ResponseEntity.ok(portfolioDTO);
     }
 
Index: backend/src/main/java/com/tradingmk/backend/model/Portfolio.java
===================================================================
--- backend/src/main/java/com/tradingmk/backend/model/Portfolio.java	(revision d12f01b171edcf326297341c70d7ad611ac288ee)
+++ backend/src/main/java/com/tradingmk/backend/model/Portfolio.java	(revision 008dcb86144595548e0692fb8ce6e571e23f86b9)
@@ -2,4 +2,5 @@
 
 
+import com.fasterxml.jackson.annotation.JsonBackReference;
 import jakarta.persistence.*;
 
@@ -16,4 +17,5 @@
     @OneToOne
     @JoinColumn(name = "user_id", nullable = false, unique = true)
+    @JsonBackReference // the back part, which will be ignored during serialization to avoid recursion
     private User user;
 
Index: backend/src/main/java/com/tradingmk/backend/model/User.java
===================================================================
--- backend/src/main/java/com/tradingmk/backend/model/User.java	(revision d12f01b171edcf326297341c70d7ad611ac288ee)
+++ backend/src/main/java/com/tradingmk/backend/model/User.java	(revision 008dcb86144595548e0692fb8ce6e571e23f86b9)
@@ -1,4 +1,5 @@
 package com.tradingmk.backend.model;
 
+import com.fasterxml.jackson.annotation.JsonManagedReference;
 import jakarta.persistence.*;
 import lombok.AllArgsConstructor;
@@ -33,5 +34,6 @@
 
 
-    @OneToOne(mappedBy = "user", cascade = CascadeType.ALL, fetch = FetchType.LAZY)
+    @OneToOne(mappedBy = "user", cascade = CascadeType.ALL)
+    @JsonManagedReference // the forward part of the relationship to serialize
     private Portfolio portfolio;
 
Index: backend/src/main/java/com/tradingmk/backend/service/UserService.java
===================================================================
--- backend/src/main/java/com/tradingmk/backend/service/UserService.java	(revision d12f01b171edcf326297341c70d7ad611ac288ee)
+++ backend/src/main/java/com/tradingmk/backend/service/UserService.java	(revision 008dcb86144595548e0692fb8ce6e571e23f86b9)
@@ -68,5 +68,5 @@
                 .setSubject(userDetails.getUsername())
                 .setIssuedAt(new Date(System.currentTimeMillis()))
-                .setExpiration(new Date(System.currentTimeMillis() + 1000 * 60 * 24))
+                .setExpiration(new Date(System.currentTimeMillis() + 1000L * 60 * 60 * 24))
                 .signWith(getSignInKey(), SignatureAlgorithm.HS256)
                 .compact();//compact genertaes the token