Skype for Business Server 2019 Deployment Issue - KB2566790

Hello,

I am setting up skype for business server 2019 standard edition deployment on prem on a test environment, everything seems to be setup correctly, but I am encountering a DNS logon issue when I attempt to sign in from the client. The name of the error message is KB2566790 and I have attached the text and a screenshot below.

I've attempted to add missing SRV and CNAME records as detailed in the below tutorial but no luck.

https://docs.microsoft.com/en-us/skypeforbusiness/troubleshoot/online-configuration/dns-configuration-issue

Any help is appreciated.

"Skype for Business couldn't find a Skype for Business Server for (domain.com). There might be an issue with the Domain Name System (DNS) configuration for your domain. See KB2566790 for details and contact your system admin."