Error: 18456, Severity: 14, State: 5; SSMS > Network sever from PC
My team lead, pointed out the issue.  As I could not find the issue/solution here, posting it for others.

I knew I could not use windows authentication, so I was trying to use SQL Server Authentication, this was the problem.

To access SSMS as a different user - When opening SSMS from your PC; Shift + right click > ‘Run as Different User’ enter ID ‘Admin1’ + password, proceed as normal.