Vw Polo 9N eats complete oil

Hello! I’m looking forward to an urgent question to you, in the hope that someone might be able to help the car… So in November 2014 I bought a polo 9N year 2002 with 133,000 km and nem 1 , 2er engine. Quite quickly the oil control light started to light up. I then replenished oil, can happen already. However, he then at 2000km eaten the complete oil. In the old invoices I have seen that the polo had a cylinder head damage, which a workshop repaired. Unfortunately, did not have the invoices and the letter available at the time I want to pay the car still in the workshop where I bought it. Well, as well as that, my father then suspected that the piston rings have stuck. So I am with the polo to the workshop where I bought it but did not give it to the workshop. The workshop didn’t suspect the same thing and so the polo sealant was getting into the oil again I’ve always got a oil change engine cleaning. Full program said that it had to be done with it. But not to give it from the 2000 km! The workshop just doesn’t know what the same oil is going to go back again!