Unable to get updated Checkboxes from uploaded Excel file in asp.net core 3.1 mvc - asp.net-core-mvc

Question

As soon as the Excel file is uploaded and clicked on Submit button, the data in the Excel file will be populated as shown in the below screenshot. Some checkboxes will be selected while some others are not, based on the conditions written in the program. Till here everything is working fine.
End user selects/un-selects checkboxes, and clicks on Process Hold Reasons button. Now, I want updated model with modified checkboxes values. I'm not even understanding how and where to write the code to achieve this. Tried number of ways, but unable to succeed.
Can someone please suggest me on this!
Below is the code in Index.cshtml page.
#model SupportTool.Models.ViewModels.EligibilityIssuesViewModel
#{
ViewData["Title"] = "Eligiblity Issues";
}
<style>
.Success {
font-weight: bold;
color: green;
font-size: 15px;
}
.Error {
font-weight: bold;
color: red;
font-size: 15px;
}
td {
height: 20px;
}
</style>
<br />
<br />
<div>
<span class="Success">#ViewBag.Success</span>
<span class="Error">#ViewBag.Error</span>
</div>
<form asp-controller="EligibilityIssues" asp-action="Index" method="post" class="form-horizontal" role="form" enctype="multipart/form-data">
<div class="form-group">
<div class="row">
<div class="alert-danger" asp-validation-summary="ModelOnly"></div>
</div>
</div>
<div class="form-group">
<div class="col-md-10">
<p>Upload Excel file:</p>
<div class="custom-file">
<input asp-for="ExportedExcelFile" class="form-control custom-file-input" />
<label class="custom-file-label">Choose file...</label>
</div>
</div>
<div class="form-group">
<div class="col-md-10">
<input type="submit" value="Submit" class="btn-success" />
</div>
</div>
</div>
#section Scripts {
<script>
$(function () {
$('.custom-file-input').on('change', function () {
var fileName = $(this).val().split('\\').pop();
$(this).next('.custom-file-label').html(fileName);
});
});
</script>
}
#if (Model != null && Model.HoldReasons != null)
{
<h1>Eligibility issues should be shown here</h1>
<table>
<thead>
<tr>
<th> </th>
<th>Hold Reasons</th>
</tr>
</thead>
<tbody>
#for (int i = 0; i < Model.HoldReasons.Count; i++)
{
<tr>
<td>
#Html.CheckBox("holdReason[" + i + "].HoldReasonShouldBeChecked", Model.HoldReasons[i].HoldReasonShouldBeChecked)
#if (!Model.HoldReasons[i].HoldReasonShouldBeChecked)
{
<span style="border: 1px solid red">
(#Model.HoldReasons[i].StateName)#Model.HoldReasons[i].HoldReason
</span>
}
else
{
<span>(#Model.HoldReasons[i].StateName)#Model.HoldReasons[i].HoldReason</span>
}
#Html.Hidden("holdReason[" + i + "].WorkOrderId", Model.HoldReasons[i].WorkOrderId)
</td>
</tr>
}
</tbody>
</table>
<input type="submit" asp-action="ProcessHoldReasons" value="Process Hold Reasons" class="btn btn-primary" />
}
</form>
Below is the Code in HomeController
namespace SupportTool.Controllers
{
public class EligibilityIssuesController : Controller
{
private readonly IEligibilityIssuesBLL _bll;
private readonly IWebHostEnvironment _hostEnvironment;
public EligibilityIssuesController(IEligibilityIssuesBLL bll, IWebHostEnvironment hostEnvironment)
{
_bll = bll ?? throw new ArgumentNullException(nameof(bll));
_hostEnvironment = hostEnvironment ?? throw new ArgumentNullException(nameof(hostEnvironment));
}
public IActionResult Index()
{
return View();
}
[HttpPost]
public IActionResult Index(EligibilityIssuesViewModel model)
{
try
{
if (ModelState.IsValid)
{
if (model.ExportedExcelFile != null)
{
var folder = Path.Combine(_hostEnvironment.WebRootPath, "uploaded_excel_files");
if (!Directory.Exists(folder))
{
Directory.CreateDirectory(folder);
}
var incomingFileName = model.ExportedExcelFile.FileName;
model.UploadedExcelFileName = Path.Combine(folder, incomingFileName);
using (var fileStream = new FileStream(model.UploadedExcelFileName, FileMode.Create))
{
model.ExportedExcelFile.CopyTo(fileStream);
}
model.HoldReasons = _bll.GetHoldReasons(model);
}
return View(model);
}
return View(model);
}
catch (Exception ex)
{
ViewBag.Error = new HtmlString(#"Unexpected error occurred. Below is the message for your verification:<br />"
+ ex.Message);
return View(model);
}
}
}
}