In reply to:
it put my account balance in negative and says i owe the new balance on the 6th of june, cutting my plan short 4 month and probably my luck a year and four months!
I don't think you actually lose any of the time remaining on your previous plan. As I understand it, when you change the billing period any unused pre-payment is credited towards the new price and your plans billing start date is changed to the day that you make the changes.
So you should not have been charged the full 2 year cost and the panel should show the 'Paid Thru (end date)' as 24 months from the date that you made the changes.
Mark
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