If you would like to block certain numbers so that they cannot be dialed from the system, you can do it from 'Disabled routes'.

Navigate to 'Routes->Disabled routes' and type in the numbers that you want to block.

Destinations should be seperated by new lines.

Regular expressions can be used by prefixing the destination with "_" (e.g. _^001[2-9]).

Please note that any numbers that you enter into Disabled routes will be blocked on all system levels.