I'm having the same error. See the following code.

$settings = [
    'auth_mode' => 'oauth2',
    'ClientID' => 'client id',
    'ClientSecret' => 'client secret',
    'RedirectURI' => 'http://example.test/redirect',
    'accessTokenKey' => 'token key',
    'refreshTokenKey' => 'refresh token key',
    'QBORealmID' => 'my realm',
    'scope' => 'com.intuit.quickbooks.accounting',
    'baseUrl' => 'Development'
];
$dataService = DataService::Configure($settings);

$OAuth2LoginHelper = $dataService->getOAuth2LoginHelper();

try {
    $refreshedAccessTokenObj = $OAuth2LoginHelper->refreshToken();
} catch (\Exception $exception) {
   // throws exception, answer from QBO
   // Incorrect Token type or clientID
    var_dump($exception);
}

$error = $OAuth2LoginHelper->getLastError();
if($error){
    echo 'got error'.PHP_EOL;
    var_dump($error);
} else {
    echo 'update auth token'.PHP_EOL;
    //Refresh Token is called successfully
    $dataService->updateOAuth2Token($refreshedAccessTokenObj);
}

// the token is valid
// I can see company info
echo 'get company info'.PHP_EOL;
print_r($dataService->getCompanyInfo());