If you have bought a Flowcode key from Matrix then it should appear in the form:
The first step is to ensure you have a Matrix account, you can register for a Matrix account here:
Next step is to login to that account:
Finally you want to attach the key you purchased to your account, this can be done by visiting this page here and copying the key into the box provided, if you have not set up a Flowcode 7 account before, you will also need to type in a Flowcode username, this is simply an aesthetic name which will show who the software is registered to:
Once you have clicked "Confirm" this will update your licence on our servers and you can then go into Flowcode and go to Help >> Activate and type in your username and password to update your licence.