Not able to generate report in kibana7.6.1 in PDF as well as PNG form

I have installed ELK 7.6.1 and heartbeat 7.6.1 . Created dashboard for heartbeat and trying to create report in PDF as well as PNG format using share option but it is not working getting some error attached in screenshot. Also when i click on "Copy Post URL" and open that url in browser , it give {"statusCode":405,"error":"Method Not Allowed","message":"GET is not allowed"} in response.

The URL from the link doesn't work in the browser as it's POST request to be used in Alerting/Watcher. The reports that you generate should show up in Management -> Reporting. Also any errors should show up there as well on the details.

In Management-> Reporting tab , reports are generating when i execute watcher through Dev Tool but now i am getting error,
{"statusCode":504,"error":"Gateway Time-out","message":"Client request timeout"} .

I have increase xpack.reporting.queue.timeout: 200000 value from 120000 to 200000 in kibana.yml. Is there any setting i have to add in yml file ?