If you are a Builder Club member, you will receive the daily stipend of Robux once every 24 hours. Robux stipends are given whether you log in or not.
You can check and see that you received your Robux by going to the Summary tab of your Trade section.
Note: The Past Day is what you got today. Past Week is the past week. Past Month is the past 30 days. Past Year is all of the Robux you have received over the past 365 days.