Microsoft point cards

I am very angry with xbox, they are cheating me out of point cards. I have a bunch of them, some still with receipts directly from Microsoft store and they tell me they are no longer valid and I am supposed to lose out a on around 200$ worth of points! They have no expiration dates on them and when they looked them up they could still see the funds on the codes. I call in and get hung up on, and they never emailed back after a long online chat!

This is disgusting service from a huge company like Microsoft.

:)