Hii my name is Luna Fallon i am from the technical team if you are facing a problem then you can visit our site. If your Brother wireless printer is offline, it could be due to several reasons. One of the most common reasons is a poor or unstable network connection. If the printer is not properly connected to the network, it may go offline. Another reason could be outdated printer drivers, which can cause communication issues between the printer and computer. Power management settings such as sleep mode or power saving mode can also cause the printer to disconnect from the network.