How do I find out what is causing the app "Google" to use so much background data Even though I have background data turned off, it is using incredibly high amounts of data to the point of being ridiculous. This is starting to cost me money as data is not unlimited in Canada. It's gotten to the point where I can't use data because if I turn it on Google just gobbles it all up. At one point, it was just full tilt downloading/uploading something I have no idea what it would be. 

What is causing this and/or how can I turn off background usage for Google for real (obviously the toggle is a placebo)

Screenshots of data usage.
As an update to this: I never figured out the exact problem that caused this. Even after turning off features like google assistant it still continued to use an unusually high bandwidth. The eventual solution was rooting + custom kernel + custom ROMs. I don't have any issues now.