in application.conf
db {
default.driver=com.microsoft.sqlserver.jdbc.SQLServerDriver,
default.url="jdbc:sqlserver://127.0.0.1:1541;databaseName=yourdatabasename",
default.username=username,
default.password="password"
}

port of your mssql server you can find in "Sql Server Configuration Manager", my was mssql server was using port 1541