Testing truncates MySql database

Hi - I'm early in my learning TDD. I've set up my testing environment to use the in-memory sqlite database, but when I run my tests, the actual MySql database gets wiped out as well. Any thoughts on what I can look for that is triggering this? Here's the phpunit.xml file:

<?xml version="1.0" encoding="UTF-8"?>
<phpunit xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:noNamespaceSchemaLocation="./vendor/phpunit/phpunit/phpunit.xsd"
         bootstrap="vendor/autoload.php"
         colors="true"
>
    <testsuites>
        <testsuite name="Unit">
            <directory suffix="Test.php">./tests/Unit</directory>
        </testsuite>
        <testsuite name="Feature">
            <directory suffix="Test.php">./tests/Feature</directory>
        </testsuite>
    </testsuites>
    <coverage processUncoveredFiles="true">
        <include>
            <directory suffix=".php">./app</directory>
        </include>
    </coverage>
    <php>
        <env name="APP_ENV" value="testing"/>
        <env name="BCRYPT_ROUNDS" value="4"/>
        <env name="CACHE_DRIVER" value="array"/>
        <env name="DB_CONNECTION" value="sqlite"/>
        <env name="DB_DATABASE" value=":memory:"/>
        <env name="MAIL_MAILER" value="array"/>
        <env name="QUEUE_CONNECTION" value="sync"/>
        <env name="SESSION_DRIVER" value="array"/>
        <env name="TELESCOPE_ENABLED" value="false"/>
    </php>
</phpunit>

Here's an example test:

<?php

namespace Tests\Feature;

use App\Models\User;
use Illuminate\Foundation\Testing\WithFaker;
use Tests\TestCase;

class ProfilePageTest extends TestCase
{
    public function test_page_will_not_open_for_guest()
    {
        $response = $this->get('profile/3');

        $response->assertRedirect('login');
    }

    public function test_page_will_open_for_auth_user()
    {
        $this->withoutExceptionHandling();

		$this-refreshDatabase();

        $user = User::factory()->create();

        auth()->loginUsingId($user->id);

        $response = $this->get(route('profile',['user' => $user]));

        $response->assertViewIs('users.profile');
    }
}

I have the RefreshDatabase in the TestCase model

<?php

namespace Tests;

use Illuminate\Foundation\Testing\RefreshDatabase;
use Illuminate\Foundation\Testing\TestCase as BaseTestCase;

abstract class TestCase extends BaseTestCase
{
    use CreatesApplication;
    use RefreshDatabase;
}

I didn't have the DB_CONNECTION and DB_DATABASE uncommented on my first few tests, so I understood why I was losing my data then, but I can't figure it out now. Thanks for your help!