Please be aware that these are public forums and confidential data, like serial numbers, should never be posted here. Hence I have edited your post.
No-one who posts here is a Magix employee; you need to email infoservice@magix.net with details of your purchase and ask that they check your serial number for ACID 11. As @johnebaker wrote, are you certain you have installed the correct version AND edition of ACID that you purchased? The green tick indicates the serial key is "valid" but apparently not for the product you have.
Thank-you for your swift reply. I wasn't sure about sending the serial numbers. It won't happen again. I was just frustrated about the delay I'm having in getting important work done on time. I've been working with ACID for over twenty years. How do I know if I've installed the correct version and edition? I'm working on a new computer that is capable of any Magix product.