The rise in cost from £59to£99

[Par3]

Why has it gone up so much 

[Daniel0210]

@Par3 
Could your previously discounted deals have expired? You would have been notified of their end date when you first took them out but at present you don’t get reminders prior to them ending. Compare a previous bill to your latest bill and see where the amounts differ.
If the discounts have ended you will need to call Sky to try to negotiate a new deal which will require another minimum term contract, although Sky are not obliged to offer you another discount. If you sort something to your satisfaction make a note of the date it’s ending.

https://www.sky.com/help/articles/been-overcharged may help explain.

Also factor in the annual price increase effective from April’s bills in the UK.