SQL Connection: Cannot open server "example.com" requested by the login. The login failed

Question

I am attempting to establish a connection to SQL Server with this connection string:

new SqlConnection("Server=tcp:myServer.net,1433;Database=myDatabase;
Trusted_Connection=False;Encrypt=True;MultipleActiveResultSets=True;
User [email protected];Password=SomePassword123")
       .Open();

But I keep getting this error. It's like it doesn't respect the @ symbol as part of the username. I tried single quotes, double quotes, and two @@ symbols to see if any of that would escape it but still gives this error about the domain name. It's just part of the username.

Class: 20
    ClientConnectionId: {b9d66561-5e69-4a01-840d-86eb9b3066f9}
    Data: {System.Collections.ListDictionaryInternal}
    ErrorCode: -2146232060
    Errors: {System.Data.SqlClient.SqlErrorCollection}
    HResult: -2146232060
    HelpLink: null
    InnerException: null
    IsTransient: false
    LineNumber: 0
    Message: "Cannot open server \"example.com\" requested by the login.  The login failed."
    Number: 40532
    Procedure: ""
    Server: "tcp:myServer.net,1433"
    Source: "Core .Net SqlClient Data Provider"
    SqlState: null
    StackTrace: "   at System.Data.ProviderBase.DbConnectionPool.CheckPoolBlockingPeriod(Exception e)\r\n   at System.Data.ProviderBase.DbConnectionPool.CreateObject(DbConnection owningObject, DbConnectionOptions userOptions, DbConnectionInternal oldConnection)\r\n   at System.Data.ProviderBase.DbConnectionPool.UserCreateRequest(DbConnection owningObject, DbConnectionOptions userOptions, DbConnectionInternal oldConnection)\r\n   at System.Data.ProviderBase.DbConnectionPool.TryGetConnection(DbConnection owningObject, UInt32 waitForMultipleObjectsTimeout, Boolean allowCreate, Boolean onlyOneCheckConnection, DbConnectionOptions userOptions, DbConnectionInternal& connection)\r\n   at System.Data.ProviderBase.DbConnectionPool.TryGetConnection(DbConnection owningObject, TaskCompletionSource`1 retry, DbConnectionOptions userOptions, DbConnectionInternal& connection)\r\n   at System.Data.ProviderBase.DbConnectionFactory.TryGetConnection(DbConnection owningConnection, TaskCompletionSource`1 retry, DbConnectionOptions u
serOptions, DbConnectionInternal oldConnection, DbConnectionInternal& connection)\r\n   at System.Data.ProviderBase.DbConnectionInternal.TryOpenConnectionInternal(DbConnection outerConnection, DbConnectionFactory connectionFactory, TaskCompletionSource`1 retry, DbConnectionOptions userOptions)\r\n   at System.Data.ProviderBase.DbConnectionClosed.TryOpenConnection(DbConnection outerConnection, DbConnectionFactory connectionFactory, TaskCompletionSource`1 retry, DbConnectionOptions userOptions)\r\n   at System.Data.SqlClient.SqlConnection.TryOpen(TaskCompletionSource`1 retry)\r\n   at System.Data.SqlClient.SqlConnection.Open()"
    State: 1