On my desktop pc, running Zorin OS Pro, my scanner is no longer found by the desktop scanner program. Had worked perfectly for months now. It's a wireless network printer (Brother), prints well, no issues with connectivity.
On a laptop running ZorinOS16 Core, which has not been updated for a few weeks now, the same scanner software detects the scanner and scans perfectly.
As another point of interest, on my wife's Linux Mint laptop, she has also lost the connectivity to the scanner.
I have a Canon all-in-one and have had issues with Document Scanner not working at all for some time. The Canon driver works but is very simplistic so I splashed out on VueScan - it is pricey granted but it just works! It is also cross-platform. One reviewer was using Windows 10 and a 30 year old Epson Scanner without any issues.
Interesting ..... $27.50 ain't to bad but seeing as I have to get up to put the item to be scanned in my Brother scanner any way I just push the scan button on the unit OR use my secret weapon ...................... ask the Mrs ................ to do it .....
Now you may have to solve a problem with the scanner. In 64-bit Linux Mint 19.x and Ubuntu 18.04 the location for the supporting library files has changed, and the driver for the scanner feature doesn't always take that into account. The Brother driver then puts them in /usr/lib64, whereas your operating system expects them in /usr/lib. (from a Mint forum)
On my Zorin system, the scanner was back to operational.
On my wifes Mint system, the grep returned a printer with a wrong IP address. Running the brsaneconfig4 command with the -r switch removed it, and after following up with a reinstall everything was fine