Unable to get Ubidots values with PHP


Hi all!
I am new here, I just started my project I have execute the php code in order to getvalues form ubidots.
When I used the example in The Ubidots PHP API Client I tried to save values then I got the problem :

//***********code.php ****************
require 'vendor/autoload.php';

$api = new Ubidots\ApiClient($apikey="A1E-5ab87fe22a1b8609304ae8620f9400b9ac92");
/* Get all variables */
$all_datasources = $api->get_datasources();

$my_variable = $api->get_variable('5a6c9a26c03f9764e297dac3');

$some_values = $my_variable->get_values(10);

//********** command runing code********
C:\php>php.exe test\ubidots-php-master\code.php
PHP Warning: range(): step exceeds the specified range in C:\php\te
st\ubidots-php-master\src\Ubidots\Paginator.php on line 29
PHP Warning: Invalid argument supplied for foreach() in C:\php\test\ubidots-php
-master\src\Ubidots\Paginator.php on line 29

PHP Warning: array_values() expects parameter 1 to be array, boolean given in C
:\php\test\ubidots-php-master\src\Ubidots\Paginator.php on line 132
PHP Warning: array_slice() expects parameter 1 to be array, null given in C:\ph
p\test\ubidots-php-master\src\Ubidots\Paginator.php on line 103