diff --git a/src/main/java/de/zendric/app/xpensely_server/services/ExpenseListService.java b/src/main/java/de/zendric/app/xpensely_server/services/ExpenseListService.java
index 284e89f..0f65b6e 100644
--- a/src/main/java/de/zendric/app/xpensely_server/services/ExpenseListService.java
+++ b/src/main/java/de/zendric/app/xpensely_server/services/ExpenseListService.java
@@ -117,7 +117,7 @@ public class ExpenseListService {
 
     public Expense updateExpense(Long expenseListId, Expense updatedExpense) {
         ExpenseList expenseList = repository.findById(expenseListId)
-                .orElseThrow(() -> new IllegalArgumentException("ExpenseList not found"));
+                .orElseThrow(() -> new ResourceNotFoundException("ExpenseList not found with id: " + expenseListId));
 
         if (!expenseList.getExpenses().stream()
                 .anyMatch(expense -> expense.getId().equals(updatedExpense.getId()))) {
@@ -125,7 +125,7 @@ public class ExpenseListService {
         }
 
         Expense existingExpense = expenseRepository.findById(updatedExpense.getId())
-                .orElseThrow(() -> new IllegalArgumentException("Expense not found"));
+                .orElseThrow(() -> new ResourceNotFoundException("Expense not found with id: " + updatedExpense.getId()));
         existingExpense.setTitle(updatedExpense.getTitle());
         existingExpense.setAmount(updatedExpense.getAmount());
         existingExpense.setPersonalUseAmount(updatedExpense.getPersonalUseAmount());
@@ -151,7 +151,7 @@ public class ExpenseListService {
         XpenselyCustomCategory category = customCategoryRepository.findById(categoryId)
                 .orElseThrow(() -> new ResourceNotFoundException("Custom Category not found"));
         if (!category.getExpenseList().getId().equals(expenseListId)) {
-            throw new RuntimeException("Category does not belong to the specified Expense List");
+            throw new IllegalArgumentException("Category does not belong to the specified Expense List");
         }
         customCategoryRepository.delete(category);
     }