tabel relasi tidak dapat memunculkan isi dari tabel

    public function nilai($Nim)
    {
        $Mahasiswa = Mahasiswa::with('kelas')->where('nim', $Nim)->first();
        $matkul = Mahasiswa_MataKuliah::with('matakuliah')->where('mahasiswa_id', ($Mahasiswa->mahasiswa_id))->get();
            return view('mahasiswa.nilai', ['Mahasiswa' => $Mahasiswa, 'matakuliah' => $matkul]);
    }

<?php

namespace App\Models;

use Illuminate\Database\Eloquent\Factories\HasFactory;
use Illuminate\Database\Eloquent\Model;

class Mahasiswa_MataKuliah extends Model
{
    use HasFactory;
    protected $table = 'matakuliah_mahasiswa';
    protected $fillable = ['mahasiswa_id',
                            'matakuliah_id',
                            'nilai',
                        ];
    
    public function mahasiswa()
    {
        return $this->belongsTo(Mahasiswa::class, 'mahasiswa_id', 'id_mahasiswa');
    }

    public function matakuliah()
    {
        return $this->belongTo(Matakuliah::class, 'matakuliah_id');
    }
}

<?php

namespace Database\Seeders;

use Illuminate\Database\Seeder;
use Illuminate\Support\Facades\DB;

class MataKuliahSeeder extends Seeder
{
    /**
     * Run the database seeds.
     *
     * @return void
     */
    public function run()
    {
        $matkul = [
            [   'nama_matkul' => 'Pemrograman Berbasis Objek',
                'sks' => 3,
                'jam' => 6,
                'semester' => 4,
            ],
            [   'nama_matkul' => 'Pemrograman Web Lanjut',
                'sks' => 3,
                'jam' => 6,
                'semester' => 4,
            ],
            [   'nama_matkul' => 'Basis Data Lanjut',
                'sks' => 3,
                'jam' => 4,
                'semester' => 4,
            ],
            [   'nama_matkul' => 'Praktikum Basis Data Lanjut',
                'sks' => 3,
                'jam' => 6,
                'semester' => 4,
            ],
        ];

        DB::table('matakuliah')->insert($matkul);
    }
}

<?php

namespace Database\Seeders;

use Illuminate\Database\Seeder;
use Illuminate\Support\Facades\DB;

class MataKuliahMahasiswaSeeder extends Seeder
{
    /**
     * Run the database seeds.
     *
     * @return void
     */
    public function run()
    {
        $data = [
            [   'mahasiswa_id' => 1,
                'matakuliah_id' => 1,
                'nilai' => 88
            ],
            [   'mahasiswa_id' => 1,
                'matakuliah_id' => 2,
                'nilai' => 87
            ],
            [   'mahasiswa_id' => 1,
                'matakuliah_id' => 3,
                'nilai' => 86
            ],
            [   'mahasiswa_id' => 1,
                'matakuliah_id' => 4,
                'nilai' => 90
            ],
            [   'mahasiswa_id' => 3,
                'matakuliah_id' => 1,
                'nilai' => 88
            ],
            [   'mahasiswa_id' => 3,
                'matakuliah_id' => 2,
                'nilai' => 93
            ],
            [   'mahasiswa_id' => 3,
                'matakuliah_id' => 3,
                'nilai' => 85
            ],
            [   'mahasiswa_id' => 3,
                'matakuliah_id' => 4,
                'nilai' => 80
            ],
        ];

        DB::table('matakuliah_mahasiswa')->insert($data);
    }
}

@extends('mahasiswa.layout')

@section('content')
    <div class="row">
        <div class="col-lg-12 margin-tb">
            <div class="justify-content-center align-items-center">
                <div class="d-flex justify-content-center mt-2">
                    <h2>JURUSAN TEKNOLOGI INFORMASI</h2>
                </div>
                <div class="d-flex justify-content-center my-4">
                    <h1 class="text-center">KARTU HASIL STUDI (KHS)</h1>
                </div>
            </div>
        </div>
        <div class="text-left">
            <p><b>Nama : </b>{{ $Mahasiswa->nama }}</p>
            <p><b>Nama : </b>{{ $Mahasiswa->nim }}</p>
            <p><b>Nama : </b>{{ $Mahasiswa->kelas->nama_kelas }}</p>
        </div>

        <table class="table table-bordered">
            <tr>
                <th>Mata Kuliah</th>
                <th>SKS</th>
                <th>Semester</th>
                <th>Nilai</th>
            </tr>
            @foreach ($matakuliah as $matkul)
                <tr>
                    <td>{{ $matkul->matakuliah->nama_matkul }}</td>
                    <td>{{ $matkul->matakuliah->sks }}</td>
                    <td>{{ $matkul->matakuliah->semester }}</td>
                    <td>{{ $matkul->nilai }}</td>
                </tr>
            @endforeach
        </table>
        <a class="btn btn-success" href="{{ route('mahasiswa.index') }}">Kembali</a>
    </div>
@endsection