It's unfortunate that many business owners seem to think that if they have anti-virus on their company computers, they're safe from hackers, here's the truth. You're never 100% safe from hackers. And with antivirus alone, you're just a sitting duck. Your first line of defense must be being cautious about clicking on and opening emails. Don't click on links that look odd and don't open attachments like Word Excel, PowerPoint, or zip files that you're not expecting.
Second. Upgrade to an advanced security solution that doesn't just scan files but actively monitors strange behavior on your network and only allows certain trusted programs to run. Also, with so many people working from home and very few having a physical firewall on their home networks, you must have an advanced software firewall on your computer. Gone are the days when everyone was behind the company firewall. Fortunately, Windows has a software firewall built into its operating system that isn't great but does provide some level of protection if configured properly.
There are many other cybersecurity protections that should be installed on your company computers that you're allowed to bring home to work on so that it helps to ensure that your company computer doesn't cause a breach.
