You should be able to print any Accredible certificate yourself.
First, you need to go to your certificate. It will be at a URL like accredible.com/10000123.
On the sidebar for your certificate, click 'Download PDF'. This may take a moment, but once it is done, a PDF copy of your certificate will open up. If you are having an issue getting a PDF, you might find help here.
Once you are on the PDF, you can print the certificate by going to File > Print in your browser window. You can also save a copy of the PDF and print at your convenience in the future.