Azure File Share with point to site VPN

Hi, we have a customer that we are planning to move some files to Azure fileshare. This is a very samll customer. What we want to accomplish is to be able to connect to this fileshare from their office network but also from thier home networks. But as their ISP blocking SMB traffic, we need to set up a point to site VPN. I tested this and I got it to work from their office network (without VPN). I also managed to set it up with a VPN but here the problems start...When connecting to the VPN they connect to a private endpoint, so at the moment the only way to access the fileshare over VPN is by IP. The problem I phase is that when they connect to the fileshare from the office they use the public endpoint, so they wouldn't be able to access this over VPN. 

How can this be solved? In some way I need to get both endpoints connect to the same FQDN. They don't have a DNS server and they don't want to conect to the VPN every time they are in the office.

Please help.