Xperia z5 Mobile Data

[dotbossbank]

My phone keeps connecting to mobile data (virgin) even when I am on wifi at home. 

I have restricted all apps from background use and have narrowed it down to something in the android OS. Data Saver app says "1 app allowed to use unrestricted data!" I cannot find out what this is. Everything is set to off. Any ideas out there?  I know I can just switch my mobile data off but I want to get to the bottom of it.

[Uliwooly]

@dotbossbank

boot on safe mode, this will disable all third party apps, that will help you narrow down the issue, if its a preloaded app or a third party app.