my rewards points keep vanishing

With the Xbox Rewards program, it's impossible to have an odd number of credits pending. If you're referring to the Microsoft Rewards program, you would need to contact their customer support via their redemption page. The two programs are separate.

On the website, it says Xbox Rewards has now become Microsoft Rewards In Canada, does that means all my points just vanished? Also for the Microsoft Rewards system, is it 20 points for every dollar you spend?

i checked the transaction list nothing came up about 15 dollars rolling out

I saw your other post in the Rewards forums. If you had 1250 Rewards credits deposited, that would not have been $15.00. Rewards credits are not the same as Microsoft points so they don't have the same conversion rate. 1250 rewards credits would only be
$1.25 USD.

i should have 15 dollars right now but i have 2 i haven't spent it on anything yet so why is this happening

For help with the Rewards program, you'll need to post here -
forums.xbox.com/.../29.aspx

You can also check your transactions at
http://commerce.microsoft.com to see where your currency is going. Keep in mine that Rewards points/credits expire a year after receiving them so it could be possible that some expired if you hadn't used it for a while. If you notice anything suspicious
on the billing site you'll need to contact support.