You can block as many numbers as you want. Here is how to block a phone number.
** You must be an admin or assigned owner of the number to block inbound calls to that number.
1. Login to: manage.press8.com
2. Click on "Features"=>"Numbers"
3. You will see a list of the phone numbers associated with the account.
4. Select the telephone number that you wish to block calls on.
5. You will then be taken to a settings page for that number. Scroll all the way to the bottom to the section labeled “Caller Routes”
6. Directly to the right of where it says Caller Routes is a dark blue box that says “Add a caller route”.
7. Click the “Add a caller route” and you will see a page for Caller Route Settings.
8. In the box next to where it says “Caller number prefix” add the number that you wish to block. (do not use any dashes). Adding a description is optional.
9. In the final box that says “Forward matching calls to” needs to be set to "Hang Up Call".
10. Click "Save".
The blocked number will now show up in your call routes and you will no longer be receiving calls from that number.