It sounds like the cron is not set up. The cron will validate the license once a day normally. When you received that message when logging in, that your license revalidated, it means that it has been more than a week since it was validated. Setting up a cron job will prevent that error, and automate everything in Blesta.
Go to Settings > System > Automation. Try running the cron manually by clicking the button. If it works, you should get some output. Then, confirm that your cron job is set up properly on your server.