Kentico web farm synchronisation fails on azure load balanced servers with same IP

I am trying to use the kentico web farm synchronisation mechanism on the following configuration:

2 Azure servers configured under the same availability set and region which means they have the same Public IP address and URL.

I have added a load balanced end point on both the servers and bought a license for this domain. However, when I add both the servers in, Kentico says that "The current server is not configured for web farm synchronisation".

Even though both the servers use the same "Server Root URL" value, I have given both of them a unique server code name and saved in the relevant web configs on both the servers.

How do I resolve this issue ?

Thanks, Vishal