Paid app

Paid app

I've read https://www.manageengine.com/mobile-device-management/faq.html#a31 but I still can't add paid app to App Repository.
Below are steps I followed
Device Mgmt->App Repository->Apps->Add App->Play Store App
Search "Barcode & QR code Keyboard PRO" shown "Unavailable - Paid App"

Are there different steps to add paid app as Play Store apps?

TIA
Tuan
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