get id of nested object from form on thymeleaf

Question

i have 2 entity class, parkingUser and parkingDetails, user can have many parking details(one to many).

parkingUserobject contain: [id, firstName, lastName,parkingDetails[id, entryDate,...,user_id(FK)]] in parkingUser i had List of parkingDetails(its my FK)

@OneToMany(mappedBy = "parkingUsers", cascade = CascadeType.ALL, orphanRemoval = true)
private List<parkingDetails> parkingDetails = new ArrayList<parkingDetails>();

so now i have a thymeleaf page that recive from controller model of user and model of parking, its showing exist data on form input fields, and adding more data of exit date and exit time on the object in the c'tor on the controller that recive the form.

after that what i want to achive is to get the id of parking.id, but its send me from a form the id of user.id

my controller with prints to understood what i get from the form: (lets say i enter to form on user id =1, its create on the controoler new object of parkingDetails, and save it on db, after that i want to delete the new object that created with id 35, and the object that pass from the form of parking.id, but i cant access this data.

    @PostMapping("/saveDateAndTimeOfExitParking")
public String saveNewUserFromFormAction(
        @ModelAttribute("user") parkingUsers parkingUsers,
        @ModelAttribute("details") parkingDetails parkingDetails) {
    //need to store to details table date and time
    String str = LocalTime.now().format(DateTimeFormatter.ofPattern("HH:mm:ss"));
    System.out.println(parkingUsers);
    //parkingUsers [id=1, firstName=David, lastName=Adams, license=2356584, parkingDetails=[]]
    
    System.out.println(parkingDetails);
    //parkingDetails [id=1, entryDate=2022-05-18, entryTime=08:35:20, exitDate=null, exitTime=null, parkingUsers=null]
    
    System.out.println(parkingUsers.getParkingDetails());
    //[]
    parkingDetails d = new parkingDetails(
            parkingDetails.getEntryDate(),
            parkingDetails.getEntryTime(),
            LocalDate.now(),
            str);
    
    d.setParkingUsers(parkingUsers);
    parkingDetailsService.saveParkingUser(d);
    //store the object of parking details on new db of history
    //and then remove it from main schema
    System.out.println(d.getId());
    //35
    System.out.println(parkingDetails.getId());
    //1
    parkingDetailsService.deleteParkingEntrySession(d.getId());
    //i want to delete also the parkingDetails object from the form, but its gave me the id of parkingUser
    //parkingDetailsService.deleteParkingEntrySession(parkingDetails.getId());
    
    return "redirect:/exit";
}

my form:

<div class="formCenterAndWidth">
<form action="#" th:action="@{/saveDateAndTimeOfExitParking}" method="POST">
  <input type="hidden" th:field="*{user.id}"/>
  <div class="form-group row">
   
   <label class="col-sm-2 col-form-label">User Id:</label>
    <div class="col-sm-10">
    <input readonly class="form-control" type="text" th:field="*{user.id}">
    </div>

    <label class="col-sm-2 col-form-label">Parking Id:</label>
    <div class="col-sm-10">
    <input readonly class="form-control" type="text" th:field="*{parking.id}">
    </div>    
 
    <label class="col-sm-2 col-form-label">First Name:</label>
    <div class="col-sm-10">
    <input class="form-control" type="text" th:field="*{user.firstName}">
    </div>
        
    <label class="col-sm-2 col-form-label">Last Name:</label>
    <div class="col-sm-10">
    <input readonly class="form-control" type="text" th:field="*{user.lastName}">
    </div>
        
    <label class="col-sm-2 col-form-label" style="white-space: nowrap;">License Number</label>
    <div class="col-sm-10">
    <input readonly class="form-control" type="text" th:field="*{user.license}">
    </div>
    
    <label class="col-sm-2 col-form-label">Entry Date</label>
    <div class="col-sm-10">
    <input readonly class="form-control" type="text" th:field="*{parking.entryDate}">
    </div>  
    
    <label class="col-sm-2 col-form-label">Entry Time</label>
    <div class="col-sm-10">
    <input readonly class="form-control" type="text" th:field="*{parking.entryTime}">
    </div>  
 
    <label class="col-sm-2 col-form-label">Exit Date</label>
    <div class="col-sm-10">
    <input readonly class="form-control" type="text" th:value="${#dates.format(exitDateAndTime, 'dd-MM-yyyy')}">
    </div>  
    
    <label class="col-sm-2 col-form-label">Exit Time</label>
    <div class="col-sm-10">
    <input readonly class="form-control" type="text" th:value="${#dates.format(exitDateAndTime, 'HH:mm:ss')}">          
    </div>  
    
    <br><br>
    <button type="submit" class="btn btn-info col-7 center">Exit Car</button>    
     </div>
</form>