If your Direct Line number is getting spam calls more often than you would like to from a particular number, this feature will be useful. 

Log into the user portal and click on the Direct Line > under Configure, click on Block List.

Block: Enter the number you wish to block and click on Block. Remember to include the country and area codes whenever applicable. 

Note: key in +6511112222 to block the number individually. Or key in +65 to block all the calls from Singapore. Same as other nations

Anonymous Calls: Anonymous calls are blocked by default. Otherwise, click on the Unblock icon beside the Status.

Import from Recent Calls: View records of calls that were made to your Direct Line > select the numbers you wish to Block > then click Import.