[ERROR_MSG] => Error in Google Request

Hi there.

I just installed your plug-in and followed both all your instructions and tried to find my answer here.

But I can not get this plugin to work.
First I installed the latest version of WP and then downgraded to 4.9.9
With the same results

The error I get in the logs is : [ERROR_MSG] => Error in Google Request

see the whole log below

I tried with two Google Accounts and multiple Forms.

The email function in Contact Form 7 works fine.

Can you please help me

00:18:44 	 PHP 7.0.33 	 Array
(
    [date] => March 9, 2019 12:18 am
    [g-recaptcha-response] => 
    [your-name] => Siggi
    [your-email] => [email protected]
    [your-subject] => 1
    [your-message] => 2321
    [ERROR_MSG] => Error in Google Request
    [TRACE_STK] => #0 /home/innranetviss/public_html/sendingar/wp-content/plugins/ns-google-sheets-connector/lib/asimlqt/php-google-spreadsheet-client/src/Google/Spreadsheet/DefaultServiceRequest.php(147): Google\Spreadsheet\DefaultServiceRequest->execute(Resource id #21)
#1 /home/innranetviss/public_html/sendingar/wp-content/plugins/ns-google-sheets-connector/lib/asimlqt/php-google-spreadsheet-client/src/Google/Spreadsheet/ListFeed.php(79): Google\Spreadsheet\DefaultServiceRequest->post('https://spreads...', '<entry xmlns="h...')
#2 /home/innranetviss/public_html/sendingar/wp-content/plugins/ns-google-sheets-connector/lib/google-sheets.php(86): Google\Spreadsheet\ListFeed->insert(Array)
#3 /home/innranetviss/public_html/sendingar/wp-content/plugins/ns-google-sheets-connector/ns-google-sheets-connector.php(341): googlesheet->add_row(Array)
#4 /home/innranetviss/public_html/sendingar/wp-includes/class-wp-hook.php(286): ns_google_sheets_connector->wpcf7_send_to_sheets(Object(WPCF7_ContactForm))
#5 /home/innranetviss/public_html/sendingar/wp-includes/class-wp-hook.php(310): WP_Hook->apply_filters('', Array)
#6 /home/innranetviss/public_html/sendingar/wp-includes/plugin.php(453): WP_Hook->do_action(Array)
#7 /home/innranetviss/public_html/sendingar/wp-content/plugins/contact-form-7/includes/submission.php(213): do_action('wpcf7_mail_sent', Object(WPCF7_ContactForm))
#8 /home/innranetviss/public_html/sendingar/wp-content/plugins/contact-form-7/includes/submission.php(33): WPCF7_Submission->submit()
#9 /home/innranetviss/public_html/sendingar/wp-content/plugins/contact-form-7/includes/contact-form.php(729): WPCF7_Submission::get_instance(Object(WPCF7_ContactForm), Array)
#10 /home/innranetviss/public_html/sendingar/wp-content/plugins/contact-form-7/includes/rest-api.php(280): WPCF7_ContactForm->submit()
#11 /home/innranetviss/public_html/sendingar/wp-includes/rest-api/class-wp-rest-server.php(936): wpcf7_rest_create_feedback(Object(WP_REST_Request))
#12 /home/innranetviss/public_html/sendingar/wp-includes/rest-api/class-wp-rest-server.php(321): WP_REST_Server->dispatch(Object(WP_REST_Request))
#13 /home/innranetviss/public_html/sendingar/wp-includes/rest-api.php(266): WP_REST_Server->serve_request('/contact-form-7...')
#14 /home/innranetviss/public_html/sendingar/wp-includes/class-wp-hook.php(286): rest_api_loaded(Object(WP))
#15 /home/innranetviss/public_html/sendingar/wp-includes/class-wp-hook.php(310): WP_Hook->apply_filters('', Array)
#16 /home/innranetviss/public_html/sendingar/wp-includes/plugin.php(515): WP_Hook->do_action(Array)
#17 /home/innranetviss/public_html/sendingar/wp-includes/class-wp.php(375): do_action_ref_array('parse_request', Array)
#18 /home/innranetviss/public_html/sendingar/wp-includes/class-wp.php(715): WP->parse_request('')
#19 /home/innranetviss/public_html/sendingar/wp-includes/functions.php(960): WP->main('')
#20 /home/innranetviss/public_html/sendingar/wp-blog-header.php(16): wp()
#21 /home/innranetviss/public_html/sendingar/index.php(17): require('/home/innranetv...')
#22 {main}
)