The type 'spatialdbcontext' does not inherit from dbcontext in .netcore while doing migrations, very urgent

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ASP.NET-Core

The type 'SpatialDbContext' does not inherit from DbContext. The DbMigrationsConfiguration.ContextType property must be set to a type that inherits from DbContext.
This is the error showing when I am enabling migrations. What can I try to fix this?
SpatialDbContext is inherited from DbContext,but it still showing above error

What I have tried:

//using Microsoft.EntityFrameworkCore;
using SpatialSample.Entities;
//using DbContext = Microsoft.EntityFrameworkCore.DbContext;
//using Microsoft.EntityFrameworkCore.Migrations;
//using GeoAPI.Geometries;
using NetTopologySuite;
using NetTopologySuite.Geometries;
using System;
//using System.Data.Entity;
using Microsoft.EntityFrameworkCore;
//using Microsoft.EntityFrameworkCore;
//using Microsoft.EntityFrameworkCore;
//using Coordinate = NetTopologySuite.Geometries.Coordinate;
//using Coordinate = GeoAPI.Geometries.Coordinate;
//using System.Data.Entity;
//using System.Data.Entity.Infrastructure;
//using Microsoft.AspNet.Identity.EntityFramework;

namespace SpatialSample
{
    public class SpatialDbContext : DbContext
    //DbContext
    {
        // public Microsoft.EntityFrameworkCore.DbSet<TouristAttraction> TouristAttractions { get; set; }
        // public DbSet<TouristAttraction> TouristAttractions { get; set; }
        public DbSet<TouristAttraction> TouristAttractions { get; set; }

        // public SpatialDbContext() : base() { }
        public SpatialDbContext(DbContextOptions options) : base(options) { }
        protected override void OnModelCreating(ModelBuilder modelBuilder)
        {
            var geometryFactory = NtsGeometryServices.Instance.CreateGeometryFactory(srid: 4326);
            //GeometryFactory gf = new GeometryFactory();

            modelBuilder.Entity<TouristAttraction>()
                .HasData(
                    new TouristAttraction
                    {
                        Id = 1,
                        Name1 = "Taj Mahal",
                        Location = (GeoAPI.Geometries.IPoint)geometryFactory.CreatePoint(new Coordinate(27.175015, 78.042155))
                    },
                    new TouristAttraction
                    {
                        Id = 2,
                        Name1 = "The Golden Temple of Amritsar",
                        Location = (GeoAPI.Geometries.IPoint)geometryFactory.CreatePoint(new Coordinate(31.619980, 74.876485))
                    },
                    new TouristAttraction
                    {
                        Id = 3,
                        Name1 = "The Red Fort, New Delhi",
                        Location = (GeoAPI.Geometries.IPoint)geometryFactory.CreatePoint(new Coordinate(28.656159, 77.241020))
                    },
                    new TouristAttraction
                    {
                        Id = 4,
                        Name1 = "The Gateway of India, Mumbai",
                        Location = (GeoAPI.Geometries.IPoint)geometryFactory.CreatePoint(new Coordinate(18.921984, 72.834654))
                    },
                    new TouristAttraction
                    {
                        Id = 5,
                        Name1 = "Mysore Palace",
                        Location = (GeoAPI.Geometries.IPoint)geometryFactory.CreatePoint(new Coordinate(12.305025, 76.655753))
                    },
                    new TouristAttraction
                    {
                        Id = 6,
                        Name1 = "Qutb Minar",
                        Location = (GeoAPI.Geometries.IPoint)geometryFactory.CreatePoint(new Coordinate(28.524475, 77.185521))
                    }
                );

        }
    }
}