Activation key has not been accepted by the server (upgraded and previous??)

Good afternoon,

I have bought the Parallel for Mac and when I've tried to activate it goes to window to activate the key. I have entered an upgrade key and then I entered it one more time as previous key as I don't have any previous key ( all check marks are green). but when I press activate then the pop-up window shows up saying that the server rejected the license and offers me to buy a license.

Please help asap. I really need to use the program but can't do it while the subscription is active and it looks okay on the website.

Thanks