Open the Sidequest desktop application- connect your device - green dot
Visit the listing page for the app your purchased and select On Itch
When the payment screen opens select - I already Purchased this as the bottom
You can then go to your Itch library and install apps you have purchased.
If you did not sign up to Itch, they should have sent you an email with a link to get your files see here: https://itch.io/docs/buying/already-bought
Alternatively, you can open Itch in your browser, download the files to your PC, and install from file, using the icon along the top right in Sidequest.
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