After installing Studio One 5 Professional via the Splice desktop app, when first opening Studio One 5 Professional, you'll see an activation screen:
This screen shows the specific Product Key tied to your Studio One 5 Rent-to-Own plan with Splice. When you activate the Product Key, you'll be required to login to a My.PreSonus account if you already have a My.PreSonus account or create a new My.PreSonus account.
What is a My.PreSonus account?
A My.PreSonus account is used to login to my.presonus.com
At my.presonus.com you can manage your activations, download additional content for Studio One and confirm the product key tied to your Rent-to-Own plan with Splice
You can see your Rent-to-Own copy of Studio One here: https://my.presonus.com/products/software
If you click on the specific version of Studio One tied to your Rent-to-Own plan, you can confirm that the version of Studio One tied to your my.presonus account is the version you installed with Splice:
This can help clear up any confusion as Splice account email addresses and My.PreSonus email addresses aren't required to match.
For example, this Splice account's email address is completely different than the My.PreSonus email address even though they are tied to the same Studio One 5 Professional Product Key under the Splice Rent-to-Own plan.
If you are unable to locate the My.PreSonus account tied to your Splice Rent-to-Own plan, reach out to PreSonus directly with your Product Key using the methods detailed here: https://www.presonus.com/support/Contact-Technical-Support