How to configure SQL Server Port on multiple instances?

Question

I have a server called SQLDWDEV01, with 2 instances: default and UAT.

To the default instance that uses port 1433, everything works fine.

However, the UAT instace, which I configured according to the pictures below, I cannot connect from my local machine.

I have access, and remote connections are enabled.

What is it that I miss doing so that I could connect to this instance?

If this question is somehow not complete, please ask and I will reply.

there are no firewall(s).

The error message that I am currently having is:

Cannot connect to sqldwdev01\UAT.
A network-related or instance-specific error occurred while establishing a connection to SQL Server. The server was not found or was not accessible. Verify that the instance name is correct and that SQL Server is configured to allow remote connections. (provider: SQL Network Interfaces, error: 26 - Error Locating Server/Instance Specified) (Microsoft SQL Server, Error: -1)

Answer 1

have fixed sqldwdev01 the reason I couldn't connect to UAT instance is because of a couple of reasons

1. there was a dynamic port specified for the instance under SSNetworkConfig\Protocols for UAT, so had to remove that and specify 1435 (as 1434 is in use) then restart the service
2. still cant connect remotely to the instance name but can connect using the port name eg sqldwdev01,1435 so it needed sql browser service to be running to direct the port for connecting with instance name

i started sql browser and now can connect using sqldwdev01\uat