ODOO 12 - HAVING ISSUE SENDING INVOICES

Need someone to troubleshoot Odoo 12 system having trouble sending out invoices, Error: Odoo Server Error Traceback (most recent call last): File "/opt/odoo12/xxaddons/sms_frame_ringcentral/models/ringcentral/http/[login to view URL]", line 28, in send [login to view URL]().raise_for_status() File "/opt/odoo12/odoo-venv/lib/python3.6/site-packages/requests/[login to view URL]", line 940, in raise_for_status raise HTTPError(http_error_msg, response=self) [login to view URL]: 400 Client Error: Bad Request for url: [login to view URL]~/extension/~/sms During handling of the above exception, another exception occurred: Traceback (most recent call last): File "/opt/odoo12/odoo/odoo/[login to view URL]", line 654, in _handle_exception return super(JsonRequest, self)._handle_exception(exception) File "/opt/odoo12/odoo/odoo/[login to view URL]", line 312, in _handle_exception raise [login to view URL](type(exception), exception, sys.exc_info()[2]) File "/opt/odoo12/odoo/odoo/tools/[login to view URL]", line 87, in reraise raise value File "/opt/odoo12/odoo/odoo/[login to view URL]", line 696, in dispatch result = self._call_function(**[login to view URL]) File "/opt/odoo12/odoo/odoo/[login to view URL]", line 344, in _call_function return checked_call([login to view URL], *args, **kwargs) File "/opt/odoo12/odoo/odoo/service/[login to view URL]", line 97, in wrapper return f(dbname, *args, **kwargs) File "/opt/odoo12/odoo/odoo/[login to view URL]", line 337, in checked_call result = [login to view URL](*a, **kw) File "/opt/odoo12/odoo/odoo/[login to view URL]", line 939, in __call__ return [login to view URL](*args, **kw) File "/opt/odoo12/odoo/odoo/[login to view URL]", line 517, in response_wrap response = f(*args, **kw) File "/opt/odoo12/odoo/addons/web/controllers/[login to view URL]", line 966, in call_button action = self._call_kw(model, method, args, {}) File "/opt/odoo12/odoo/addons/web/controllers/[login to view URL]", line 954, in _call_kw return call_kw([login to view URL][model], method, args, kwargs) File "/opt/odoo12/odoo/odoo/[login to view URL]", line 749, in call_kw return _call_kw_multi(method, model, args, kwargs) File "/opt/odoo12/odoo/odoo/[login to view URL]", line 736, in _call_kw_multi result = method(recs, *args, **kwargs) File "/opt/odoo12/odoo/addons/mail/wizard/[login to view URL]", line 193, in action_send_mail self.send_mail() File "/opt/odoo12/odoo/addons/website_sale/models/[login to view URL]", line 21, in send_mail return super(MailComposeMessage, self).send_mail(auto_commit=auto_commit) File "/opt/odoo12/odoo/addons/mail/wizard/[login to view URL]", line 267, in send_mail [login to view URL](res_id).message_post(**post_params) File "/opt/odoo12/odoo/addons/sale/models/[login to view URL]", line 641, in message_post [login to view URL](lambda o: [login to view URL] == 'draft').with_context(tracking_disable=True).write({'state': 'sent'}) File "/opt/odoo12/xxaddons/kanak_services_appointment/models/[login to view URL]", line 180, in write res = super(sale_order, self).write(values) File "/opt/odoo12/xxaddons/sms_frame_ringcentral/models/[login to view URL]", line 31, in write sms_templates.send_multiple_sms([login to view URL]) File "/opt/odoo12/xxaddons/sms_frame_ringcentral/models/[login to view URL]", line 75, in send_multiple_sms media_filename=sms_template.media_filename) File "/opt/odoo12/xxaddons/sms_frame/models/[login to view URL]", line 28, in send_message media_filename=media_filename) File "/opt/odoo12/xxaddons/sms_frame_ringcentral/models/[login to view URL]", line 55, in send_message response = [login to view URL]('/restapi/v1.0/account/~/extension/~/sms', payload) File "/opt/odoo12/xxaddons/sms_frame_ringcentral/models/ringcentral/platform/[login to view URL]", line 157, in post return self.send_request(request, skip_auth_check=skip_auth_check)