Unable to import models in service interface

namespace ASPNETCoreLearn2.Models
{
    public class CityWeather
    {
        public string CityUniqueCode { get; set; }
        public string CityName { get; set; }
        public DateTime DateAndTime { get; set; }
        public int TemperatureFahrenheit {  get; set; }
    }
}

using ASPNETCoreLearn2.Models; //TYPE OR NAMESPACE COULD NOT BE FOUND
namespace ServiceContracts
{
    public interface IWeatherService
    {
        public List<CityWeather> GetWeatherDetails();
    }
}