Data missing but router off

I so hate MTN right now, they have been taking my data for no reason. I have a contract that includes a router and everytime i log on to the App it shows that i used 9gig within minutes of switching it on, then i decided to switch it off for 2 days (15 & 16 April 2020), but guess what? When i check on the App it says i used 1,9 gig on the 16th and by that time the router is off for 2 days. I want MTN to cancel the contract and stop loading data each month, i’ll continue paying for the router but as for data, NO THANK YOU.