Can I block the calls and can I remove the block?
Placing a block can be done in a few ways, and should only be done in seriousness as it is not always an easy process to remove the block. You have the option to block calls from the facility when a call from the facility comes in. If you listen, that is one of the options given with the recording. Another option is to contact the provider (Usually MCI or CBS) and request a block.
Either of those options can be removed, and sometimes, can be done fairly easily, but that is not always the case. It can be quite a hassle and it can cause you to miss calls from your loved on unintentionally. Remember, you can always hang up if you don't want to accept the call at that time.