Error In Update Record (The instance of entity type 'x' cannot be tracked)

Question

I have this error when update record in RoleRepository.cs. what's the problem ?

The instance of entity type 'ApplicationRole' cannot be tracked because another instance with the same key value for {'Id'} is already being tracked. When attaching existing entities, ensure that only one entity instance with a given key value is attached. Consider using 'DbContextOptionsBuilder.EnableSensitiveDataLogging' to see the conflicting key values.

RoleController.cs

  public async Task<IActionResult> Edit(RoleViewModel role)
    {                  
            if (await _roleService.ExsistNameAsync(role))
            {
               //show message duplicate name
            }
            await _roleService.UpdateAsync(role);
            return Json(new { res = true, model = role });
        
    }

RoleService.cs

  public async Task<IdentityResult> UpdateAsync(RoleViewModel role)
    {
        var mapped = ObjectMapper.Mapper.Map<ApplicationRole>(role);
        return await _roleRepository.UpdateAsync(mapped);
    }

RoleRepository.cs

 public async Task<IdentityResult> UpdateAsync(ApplicationRole role)
    {
        return await _roleManager.UpdateAsync(role);
    }