******* customers

I took a wifi router in april.paid my first installment in May.now the amount due is extra with 1500.i am being told i used the allocated bundles.i then used out of bundles of 1500.how can i have a limit that i have no idea i have.it was set to 1500 which i have no idea of.this is unfair that once i finish my bundles then they going to charge me without me knowing