Here are ways to sort out the Printer Offline Brother issue:
The search field on the Windows 10 start button is where you type "Printers & Scanners."
Select your printer model from the Printers Settings screen on Windows.
Choose Run the troubleshooter in addition.
Windows 10 first notices an issue ( Checking for errors).
When you wait, Windows 10 will indicate that the printer is not connected.
To fix a problem if it appears in this window, click next.
With the final click, the troubleshooter is shut down.
Print a practice page.