Problem with BulkSMS (not send any SMS to users)

HI Team,

We have registered with ‘Bulk SMS’ and integrated the plugin in ‘Woocommerce’ at the back end. So our requirement is when a user shops/purchases the product then the user should receive SMS notification. We tested few times but the user is not receiving the notification. Instead we are receiving the below error message. Can you guide us in this?

Gateway answer:
Array
(
[headers] => Requests_Utility_CaseInsensitiveDictionary Object
(
[data:protected] => Array
(
[date] => Sat, 09 Sep 2017 12:13:23 GMT
[server] => Jetty(6.1.18)
[expires] => Sat, 06 May 1995 12:00:00 GMT
[cache-control] => Array
(
[0] => no-store, no-cache, must-revalidate
[1] => post-check=0, pre-check=0
)

[pragma] => no-cache
[content-type] => text/plain; charset=iso-8859-1
[content-length] => 72
)

)

[body] => 24|allow_concat_text_sms not yet supported for 16-bit Unicode messages|

[response] => Array
(
[code] => 200
[message] => OK
)

[cookies] => Array
(
)

[filename] =>
[http_response] => WP_HTTP_Requests_Response Object
(
[response:protected] => Requests_Response Object
(
[body] => 24|allow_concat_text_sms not yet supported for 16-bit Unicode messages|

[raw] => HTTP/1.1 200 OK
Date: Sat, 09 Sep 2017 12:13:23 GMT
Server: Jetty(6.1.18)
Expires: Sat, 06 May 1995 12:00:00 GMT
Cache-Control: no-store, no-cache, must-revalidate
Cache-Control: post-check=0, pre-check=0
Pragma: no-cache
Content-Type: text/plain; charset=iso-8859-1
Content-Length: 72
Connection: close

24|allow_concat_text_sms not yet supported for 16-bit Unicode messages|

[headers] => Requests_Response_Headers Object
(
[data:protected] => Array
(
[date] => Array
(
[0] => Sat, 09 Sep 2017 12:13:23 GMT
)

[server] => Array
(
[0] => Jetty(6.1.18)
)

[expires] => Array
(
[0] => Sat, 06 May 1995 12:00:00 GMT
)

[cache-control] => Array
(
[0] => no-store, no-cache, must-revalidate
[1] => post-check=0, pre-check=0
)

[pragma] => Array
(
[0] => no-cache
)

[content-type] => Array
(
[0] => text/plain; charset=iso-8859-1
)

[content-length] => Array
(
[0] => 72
)

)

)

[status_code] => 200
[protocol_version] => 1.1
[success] => 1
[redirects] => 0
[url] => https://bulksms.vsms.net/eapi/submission/send_sms/2/2.0
[history] => Array
(
)

[cookies] => Requests_Cookie_Jar Object
(
[cookies:protected] => Array
(
)

)

)

[filename:protected] =>
[data] =>
[headers] =>
[status] =>
)

)

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