I have cubase ai 10 and when I saw an upgarde to 10.5 available at a reduced price I jumped at the chance. I paid £10 for this and it took some time to download. I received the security code and entered but it did not work. I then realised I had downloaded the wrong one and it should have been to £25 upgrade and not the £10 one. I have emailed for assistance as I don’t want to pay extra (having already lost £10). I wondered if anyone can assist. I love using cubase and have done so for a long time.