Did my car break fuelly?
 

I have a long range plug-in hybrid which runs on the battery for 99% of the mileage. I filled up recently, and my statistics were not updated. The last fill up had to be a ridiculous number, about 5000 MPG. I know it doesn't make much sense, but it is what it is. Did I hit the MPG or some other limit?
Bimmer (BMW i3) | Fuelly

Yes, the limit is 399 or 400 MPG.

I was at 756 MPG before this fuel up.

I multiplied my gallons by 100. Seems to work.

Fuelly isn't set up for tracking fuel use in a bi-fuel vehicle like a PHEV. Including the grid powered miles for calculating gasoline fuel economy isn't accurate.

Fuelly is more suited to conventional vehicles. A car that uses electricity 99% of the time won't work, especially when the fuel you put in only powers a generator to recharge the battery, like in your i3.