Your user data shows you as having purchased the software so you should also have the email confirming the purchase and giving you the serial key.
Can you clarify exactly what you mean when you write that you had the software downloaded on my computer please? Do you mean you had downloaded the Installation Manager only, or had you actually installed the software? If you had installed it, did you also register and activate it with the supplied serial key?
Also, can you explain in more detail what you mean when you say when I try to redownload it it will not let me? What happens, what error message, if any, do you see?
Finally, (and sorry for all the questions but the more you tell us the more likely we are to be able to help you!) please tell us more about your computer, especially which version of Windows you have.