Grafana integration alert in rocketchat

I tried to set up notifications from grafana to rocket chat, through the type - slack, but when I send a test notification, I get an error:

t=2021-06-25T12:54:02+0000 lvl=eror msg="Request error" logger=context userId=1 orgId=1 uname=admin error="interface conversion: interface {} is nil, not bool" ....
t=2021-06-25T12:54:02+0000 lvl=eror msg="Request Completed" logger=context userId=1 orgId=1 uname=admin method=POST path=/api/alert-notifications/test status=500

for rocket chat created a webhook and added Script

class Script {

    process_incoming_request({ request }) {

        request.content.attachments.forEach(function (attachment) {
            attachment.fields.forEach(function (field) {
                field.value = field.value.toString();

        return request;


grafana version 8.0.2
rocketchat version 3.15.1

help me set up notifications from grafana in rocket chat correctly