View Contextual Filter format for Block
Mainly contextual filter works with /blog/page/[contextual filter id] e.g. /blog/page/2

By default its hard to pass the contextual filter id to a block, but you can do it this way

If you have url blog/page/2 then you can set this as shown in the image(3rd argument is 2 that will  be passed to view block ), also add necessary relations accordingly.

Hope it will help you.