You have many options. On most Android Smartphones they have the " Reject" list which can let you add a number & gets rejected. The problem with that it goes straight to your voicemail. That is the downfall. There are a few apps in the Play Store which will let you block numbers & won't go to your voicemail but give them " This customer is not available at the moment" memo. I know with Apple you add the number in the Reject list & blocks calls & incoming text messages which i love.
One of many ways that I like is Online Manager. It allows you to block 1 specific number, or "private/unknown" numbers and also helps you set up call forwarding when you are not at home or unique ring-tones for friends and family number calling in. All-inclusive in this 1 feature
Online Manager is considered a pick feature for home phone. So it can be part of your package or as an add-on based on the package you have. If you already have it, you just need to log into myRogers and access it.
You can find the feature details here on our website: Home & Away Online Manager
Hope this helps,