No way to clear the Monthly Data Limit on Huawei Mate 10 Lite, Android 7.0, EMUI 5.1

So, I'm in my 3rd month of ownership of my first (**and last**) Huawei smartphone and I have discovered yet another strange family of issues. I have a 20GB monthly data limit from work so I rarely check my data usage. But I had a few extra charges on my last bill so I decided to check it out. (First time on this phone) The first shock was that there was no Sum of the usage, just a graph with the daily peaks and that's it. So if it was say the 30th, then you would have to add-up 30 days worth of data to find out how much you have left. What a joke: Anyway, so I figure that I should add a data limit and maybe that will Sum-up my usage. So I tap on the gear icon on the top right, then on Monthly Data Limit and enter **18GB**. Voila, my total appeared: From here on, the story gets even stranger. I tapped on the pencil icon and for some strange, inexplicable reason, you can actually edit your usage. What exactly is the point of that??? So I enter a number and tap on OK to see what happens, and now the Used total becomes whatever amount I entered: So I decided to revert to the ACTUAL total usage and I was confronted with yet another trademarked Huawei irritation. You cannot clear your own usage, you have to enter something in that box, otherwise Save stays disabled: So as a last resort I thought that I should clear my data limit and be done with all this mess. Sadly I discovered that there is no way of doing that. It seems that once you enable the data limit, you're stuck with one. You can only change the number of MBs or GBs and again like above, you **have** to enter something in that box otherwise OK is disabled: I tried Network settings reset but all that does is **delete** your stored Wi-Fi networks (thanks Huawei) and Bluetooth devices (thanks again !) Any ideas?