Zoom meeting Webhook issue + TLS + Tomcat 8 java 8

Before Creating a New Topic:


API Endpoint(s) and/or Zoom API Event(s)
Webook notification URL validation call from Zoom

Description
I have subscribed for zoom events like meeting started , meeting end etc. Earlier it was working find but Zoom has made security changes after that it stopped working. When i gone through docs i found first we have to validate the end point and then it will start the notifications. Our webhook endpoint is repeatedly receiving endpoint.url_validation events, even after successfully responding with the required plainToken and encryptedToken the zoom is saying “URL validation failed. Try again later”.

I am not getting exactly what is the issue as from Zoom side we can not get the logs. I am briefing about my infra. I am using using centos7 on which i am using nginx as proxy server. The nginx is forwarding request to tomcat 8 (with java 8). If it was the issue of TLS then i think i should not get the request on my endpoint but if i am getting the control in the endpoint from Zoom URL validation button then it should be TLS problem. Please confirm if i am correct here. The response sent by me is also correct as i have checked it so is there any way i can check what is the issue.

Can anyone tell me exactly about the exact response detail like response type and or any other header aprt from the json in respnse as json is fine

Error?
Not able to validate the Webhook endpoint url. Zoom is saying URL validation failed. Try again later.