I went to book my sitter and it says on her profile that an additional dog is $10...well the price to book rang up at 2x the regular dog rate. How does the discount work and when and where does it show up? I'm much more able to pay $35 than I am $50.
My first question is have you selected dates over a holiday, that may be the reason the price jumped. Second, is one of the dogs a puppy under 1, that also may trigger a higher rate. It is also possible the booking caught a glitch when you set it up??? I would send the request to the sitter and discuss the rate and possibly the sitter will reduce it to $35 a day.
Under the service and rates on your profile, you can go to the "Additional Rates" link and change the settings for a 2nd dog so you don't have to make the changes manually.