Search not working on SharePoint Server 2019 hosted on Microsoft Azure

Hi Folks,

   Please find our SharePoint farm setup below.

1. SharePoint Server 2019 single server dev environment hosted on Azure
2. We have Alternate Access mapping as mentioned below. Since we wanted the SharePoint site to be accessed from internet, we have mapped the Azure load balancer URL to the extranet zone.

https://sp2019.contoso.lab - Default zone

https://contoso-qa.contoso.com:2019 - Extranet zone

1. When we try to perform a search it works perfectly fine inside the SharePoint server (https://sp2019.contoso.lab). However, when we try the open the site from internet (https://contoso-qa.contoso.com:2019 ) and when we try to perform a search it doesn't return any result. The site opens perfectly fine though.

In search content source we have added the below mentioned URLs,

1.https://sp2019.contoso.lab

As a part of troubleshooting these are the steps, we performed...

1. Server name mapping has been done.
2. Index reset with full crawl.
3. Search service has been restarted.
4. We do not see many issues in the crawl logs