Hii,
Try you can use the Windows app: https://apps.microsoft.com/detail/9wzdncrfj3pv?hl=en-US&gl=US
Do the following: go to the Start menu > Settings > Bluetooth & devices > Printers & scanners > Click on the printer/scanner > click on the "Scan settings" tab > "More scan and printer settings" > select the Brother printer > right-click and select "Start scan".
or
If the scanner option is missing, do the following:
Go to Start menu > Settings > Bluetooth & devices > Printers & scanners > select a Brother printer > Remove device
https://support.brother.com/g/b/downloadlist.aspx?c=us_ot&lang=en&prod=mfc8480dn_us&os=10013
Access the link below, download the full driver package, and run it as an administrator.
Try scanning and see if it works using the top feeder.
Let me know if it worked or not.
While this is not a Microsoft website, it is the official site of [MFC-8480DN/Brother].
Thanks