Re-installing Scrivener

I installed the paid version of Scrivener on 25th June this year on my laptop. It has recently had the hard drive replaced and I have been trying unsuccessfully to re-access my paid version of Scrivener since the repair. I thought I had re-installed the software but my front laptop screen keeps telling me I’ve only got the trial version, despite my putting in the License key. I’m just going round in circles and getting very frustrated. (As the License key is a mix of letters and numbers, it is not clear if “0” means the letter “O” or Zero), but I have tried both and nothing works.
Please help! Thank you.