Sorry, I misread your OP. I thought you were connecting to your office from home, but it's the other way around.
There are two possible scenarios for what you're experiencing:
You configured a full tunnel deployment at home and all traffic is being routed over the tunnel upon connection.
There are some overlapping subnets between your office and home LAN, so once you connect, traffic that would normally be routed locally via the default route is now being routed down the VPN.
If you post your server1.conf (located here -> /var/etc/openvpn), it'd be easy to verify. However, the quick check would be to go to your config and see if you have the "Redirect IPv4 Gateway" option checked. If so, unchecking it would move you to a split tunnel deployment and will now only route traffic down the tunnel that is destined for your Home LAN subnet, which should solve your issue.
If you unchecked the option or it was never checked and still have issues, then you most likely have a subnet conflict and you will have to move your home LAN to a new subnet and then reconfigured your OpenVPN server accordingly.