Debugger doesn't hit certain breakpoint – Asp.net

I’m working on a ASP.NET 5 Web API project on VS2019. I’m trying to set a breakpoint on the POST action (PostCustomerPayment) in the controller however, the breakpoint is never hit. I tried setting breakpoints in several other areas (such as the GET action and other controllers) and they work just fine. I’ve been trying to figure it out for hours and I even tried repairing visual but no luck. Any help would be really appreciated

Here is the code for the controller:

namespace IcartE1.Controllers.API
{
    [Route("api/[controller]")]
    [ApiController]
    [Authorize(AuthenticationSchemes = JwtBearerDefaults.AuthenticationScheme)]

    public class CustomerPaymentsController : ControllerBase
    {
        private readonly ApplicationDbContext _context;
        private readonly ICipherService _cipherService;

        public CustomerPaymentsController(ApplicationDbContext context,ICipherService cipherService)
        {
            _context = context;
            _cipherService = cipherService;
        }

        // GET: api/CustomerPayments
        [HttpGet]
        public async Task<ActionResult<IEnumerable<CustomerPayment>>> GetCustomerPayment()
        {
            var userId = User.FindFirstValue(ClaimTypes.NameIdentifier);
            var payments = await _context.CustomerPayment.Where(cp=> cp.CustomerId==userId).ToListAsync();
            foreach(var payment in payments)
            {
                payment.CardNumber = _cipherService.Decrypt(payment.CardNumber);
            }
            return payments;
        }

        // POST: api/CustomerPayments
        [HttpPost]
        public async Task<ActionResult<CustomerPayment>> PostCustomerPayment([FromForm] CustomerPayment customerPayment)
        {
            customerPayment.CustomerId = User.FindFirstValue(ClaimTypes.NameIdentifier);
            if (ModelState.IsValid)
            {
                customerPayment.CardNumber = _cipherService.Encrypt(customerPayment.CardNumber);
                _context.CustomerPayment.Add(customerPayment);
                await _context.SaveChangesAsync();

                return CreatedAtAction("GetCustomerPayment", new { id = customerPayment.Id }, customerPayment);
            }
            return ValidationProblem();
        }

        // DELETE: api/CustomerPayments/5
        [HttpDelete("{id}")]
        public async Task<IActionResult> DeleteCustomerPayment(int id)
        {
            var customerPayment = await _context.CustomerPayment.FindAsync(id);
            if (customerPayment == null)
            {
                return NotFound();
            }

            _context.CustomerPayment.Remove(customerPayment);
            await _context.SaveChangesAsync();

            return NoContent();
        }

        private bool CustomerPaymentExists(int id)
        {
            return _context.CustomerPayment.Any(e => e.Id == id);
        }
    }
}

EDIT: Postman Request

The model in question

public class CustomerPayment
    {
        public int Id { get; set; }

        [Required,Display(Name ="Holder Name")]
        [RegularExpression(pattern: @"^[a-zA-Z ]+$", ErrorMessage = "Holder name can only contain letters.")]
        public string HolderName { get; set; }

        [Required,Display(Name ="Card Number")]
        [CreditCard]
        public string CardNumber { get; set; }
        [Required]
        public DateTime ExpiryDate { get; set; }
        [Required]
        public string CustomerId { get; set; }
    }

EDIT 2: Because customerId was set as required the action is handled earlier so the request doesn’t hit the controller at all, removing [Required] annotation tag from customerId fixed the problem