How can I block specific phone numbers (i.e. unknown numbers, international phone numbers...)? Gogolook Service September 10, 2020 07:09 If you want to block specific phone numbers, please take the following steps: Tap “Block” on the upper left side tab. Choose the block rule you want to block. Related articles How can I block SMS? Why do I still receive calls from the blocked numbers? Why do I have to set up Whoscall as the "Default phone app"(Android7,8,9) or "Default caller ID & spam app"(and above Android10)? How can I register Whoscall? I just want to use the free trial version, why am I charged? Comments 0 comments Article is closed for comments.