How can I access a th:objects list and iterate through it with th:each?

I am trying to get access to my thymeleaf objects list and iterate through it.

The item class I am attempting to access looks like this:

data class Orders(val orders: List<Order>)
data class Order(val orderNumber: Long,
                 val time: String,
                 val name: String,
                 val zipCode: Int,
                 val recipientType: String?,
                 val recipientName: String?,
                 val recipientZipCode: String?,
                 val recipientCity: String?,
                 val shoppingNote: String?,
                 val id: Int,
                 val orderRows: List<OrderRow>)

data class OrderRow(val id: Int,
                    val variantTitle: String,
                    val productTitle: String,
                    val amount: Int,
                    val units: List<Unit>)

data class Unit(val code: String,
                val redeemed: Boolean?)

And the controller I am using to give the list of orders to my template is as follows:

@RequestMapping("/user")
    fun welcome(model: Model, principal: Principal): String {
        val user = userService.getUserInfo(principal.name)
        val listOfOrders = supplierService.getOrders(email, apiKey).orders

        model.addAttribute("user", user)
        model.addAttribute("listOfOrders", listOfOrders)

        return "user"
    }

and my template that I am using looks like this

<div class="container">
    <table class="table" th:object="${listOfOrders}">
        <thead>
        <th>#</th>
        <th>Navn</th>
        <th>ID</th>
        </thead>
        <tbody>
        <th:block th:each="order: ${listOfOrders}">
            <tr class="accordion-toggle"
                data-toggle="collapse"
                th:data-target="'#accordion_'+${order.id}">
                <td th:text="${order.orderNumber}"></td>
                <td th:text="${order.name}"></td>
                <td th:text="${order.id}"></td>
            </tr>
            <tr>
                <td></td>
                <td colspan="6">
                    <div th:id="'accordion_'+${order.id}" class="collapse in">
                        <table class="table">
                            <thead>
                            <th>#</th>
                            <th>Navn</th>
                            <th>ID</th>
                            </thead>
                            <tbody>
                            <th:block th:each="row: ${order.orderRows}">
                                <tr class="accordion-toggle"
                                    data-toggle="collapse"
                                    th:data-target="'#accordion_'+${row.id}">
                                    <td th:text="${row.amount}"></td>
                                    <td th:text="${row.productTitle}"></td>
                                    <td th:text="${row.id}"></td>
                                </tr>
                                <tr>
                                    <td></td>
                                    <td colspan="6">
                                        <div th:id="'accordion_'+${row.id}" class="collapse in">
                                            Nothing to show yet.
                                        </div>
                                    </td>
                                </tr>
                            </th:block>
                            </tbody>
                        </table>
                    </div>
                </td>
            </tr>
        </th:block>
        </tbody>
    </table>
</div>

and the first block where I use the listOfOrders as the th:object works perfectly, but for the second iteration where I try to access the orderRows of the Order fails with the two following messages

org.thymeleaf.exceptions.TemplateProcessingException: Exception evaluating SpringEL expression: "order.orderRows" (template: "user" - line 50, col 39)

org.springframework.expression.spel.SpelEvaluationException: EL1007E: Property or field 'orderRows' cannot be found on null

I am currently stuck with this, because I also need to iterate through the orderRows Units once I can iterate through the Orders orderRows.

And I have verified that the listOfOrders added to the model does indeed have both orderRows and orderRows.units.

Any suggestion as to what I am missing or suggestions to get this to work?