everytime when i try the viabtc accelerator it says "this transaction doesn't exit" ! any ideas why this is happening ?
Probably because of the low fee?
They reject transactions without the minimum fee.
Accelerating a bitcoin TX with a credit card payment is the epitome of stupidity.
You can also include paying a larger fee for an acceleration service than a bit higher tx which would have confirmed in less than an 3 blocks to that.
Accelerations services make sense only when you're not the (cheap) bastard that sent the money, you're the receiver.