Work VPN connection keeps getting disconnected

I work from home a couple days a week and up until a couple months ago I have never had a problem working remotely with my office VPN.  My IT department has checked and said that something is blocking the VPN connection.  I'm constantly having to reboot my laptop and the connection will only last for 30 minutes or so.  I'm not understanding what has changed.  Tax season is getting ready to start up and I can't have this keep happening.  It is very sporadic when it starts happening.  It has happened to my fiance'  when he tries working remotely at my house also.