I just switched to the 15$ plan that includes 250 mb data. I am at home with an internet connection. I also have a firewall to stop all data usage except for phone calls and texts. Within a couple hours of changing my plan, 5.23 mb were deducted. I received one text from Koodo thanking me for top ups. My firewall shows Android system using less than a mb of data. Why this deduction within a few hours of switching my plan? I wasn't using my phone off the internet and the browser is firewalled from data. Edit: my phone is an Umidigi F1, if that helps.