<?php

use Illuminate\Support\Facades\Schema;
use Illuminate\Database\Schema\Blueprint;
use Illuminate\Database\Migrations\Migration;

class CreateTwoFactorAuthsTable extends Migration
{
    /**
     * Run the migrations.
     *
     * @return void
     */
    public function up()
    {
        Schema::create('two_factor_auths', function (Blueprint $table) {
            $table->string('id')->nullable();
            $table->bigIncrements('user_id');
            $table->foreign('user_id')->references('id')->on('users')->onDelete('cascade');
            $table->timestamps();
        });
    }

    /**
     * Reverse the migrations.
     *
     * @return void
     */
    public function down()
    {
        Schema::dropIfExists('two_factor_auths');
    }
}

<?php

use Illuminate\Support\Facades\Schema;
use Illuminate\Database\Schema\Blueprint;
use Illuminate\Database\Migrations\Migration;

class CreateTwoFactorAuthsTable extends Migration
{
    /**
     * Run the migrations.
     *
     * @return void
     */
    public function up()
    {
        Schema::create('two_factor_auths', function (Blueprint $table) {
            $table->string('id')->nullable();
            $table->unsignedInteger('user_id');
            $table->foreign('user_id')->references('id')->on('users')->onDelete('cascade');
            $table->timestamps();
        });
    }

    /**
     * Reverse the migrations.
     *
     * @return void
     */
    public function down()
    {
        Schema::dropIfExists('two_factor_auths');
    }
}

--- 
+++ 
@@ -15,7 +15,7 @@
     {
         Schema::create('two_factor_auths', function (Blueprint $table) {
             $table->string('id')->nullable();
-            $table->unsignedInteger('user_id');
+            $table->bigIncrements('user_id');
             $table->foreign('user_id')->references('id')->on('users')->onDelete('cascade');
             $table->timestamps();
         });
Change from increments to bigIncrements (unsure if this is adviseable...)
