We've asked Google for comment, although its team is already aware of the problem. The outage has lasted for roughly a day as of this writing.
This kind of downtime would be frustrating for anyone, but it's particularly irksome for Project Fi subscribers. One of the perks of the service is its straightforward, affordable approach to data: you pay the same $10 per 1GB as you do in the US, so you're not shelling out a small fortune just to share your winter vacation on Instagram. Outages on this scale appear to be few and far between, but that's not much comfort if you're traveling and have few options for getting online when you're away from WiFi.
Update 1/14: Service appears to have been restored for some users, though it's not clear data is back for everyone.
Update 1/15: Google told us that service should be fully restored.
Source : https://www.engadget.com/2018/01/13/google-project-fi-international-data-outage/164