OK, Just got my Reply from mastercard. Since it´s been more than 120 day´s, they can´t do anything about it. They suggested to open a Claim with Paypal.
In the UK at least it's 120 days from the day you became aware of the problem. Not 120 days from payment. As Alpha failed to deliver on 31st of July as they stated many times, that is the date the chargeback clock should start running.
http://www.which.co.uk/consumer-rights/problem/how-do-i-use-chargebackTime limit There is a time limit on chargeback claims - typically 120 days - which starts from the day you become aware of a problem. There is also an overall cut off point of 540 days for Visa chargeback. Therefore, your deadline for requesting a chargeback is 120 days from discovering you have a problem, or 540 days from the transaction date, whichever comes first.