billing issue?

HI,

Last month got the info in regards upgrading my hdpvr box as i would no longer be able to get Netflix.opted to upgrade got the 4k pvr which i have not installed yet.just got my latest bill which went from $210.31 to $560.42!!!!! as far as i knew there was no charge for the upgrade.i of course called in and it seems to be sorted out we will see next month? anyway just a word to the wise i am sure this was a simple mistake?.regards mapp6868