You need to configure the MFA settings for users who connect from the Boston office.

[Reference:, https://docs.microsoft.com/en-us/azure/active-directory/conditional-access/location-condition, , Location offer your country set, IP ranges MFA trusted IP and corporate network VPN gateway IP address: This is the public IP address of the VPN device for your on-premises network. The VPN device requires an IPv4 public IP address. Specify a valid public IP address for the VPN device to which you want to connect. It must be reachable by Azure Client Address space: List the IP address ranges that you want routed to the local on-premises network through this gateway. You can add multiple address space ranges. Make sure that the ranges you specify here do not overlap with ranges of other networks your virtual network connects to, or with the address ranges of the virtual network itself., , ]