Certify doesn't post paper certificates. Your credential is digital, and its real value is the online version: anyone can open its link and confirm it is genuine, which a paper copy can't offer.
You can still have a printed copy. Log in, open your credential and download it as a PDF, then print it yourself. See How can I download and print my certificate?
Some organisations also send their own printed certificates alongside the digital version. If you'd like to know whether yours does, please ask the organisation that issued your credential.