Your Brother printer is considered to be offline when it is not communicating with your computer. This can happen for several reasons, such as a weak or lost connection, a problem with the printer driver, or a issue with the print queue. To resolve the issue, you can try the following steps: 1) Check the connection between the printer and the computer. 2) Restart both the printer and the computer. 3) Make sure the printer is set as the default printer. 4) Check the print queue for any stuck jobs and cancel them. 5) Update the printer driver. 6) Try printing from a different application.