unsolicited and automated nuisance calls

[brin6]

two phones on a joint contract, one for my wife, one for me, both phones settings identical. My wife can get between two and five unsolicited or automated nuisance calls a day, I hardly get any. My wife continuously 

blocks these calls, but they seem to have hundreds of numbers at their disposal. Is there any way, that we can only receive calls from numbers logged in our phone directory

[Kirigaya_Kazuto]

If you're on an iPhone, you can silence unknown callers in Settings -> Phone

Unfortunately there is no way to stop these and it may stop legit calls getting through

The only real way is to change numbers, which may stop it for a while, but they will come back eventually

[bristolian]

Consider yourself lucky that you don't these spam calls!

I'm in a similar position - my personal line is reasonably immune from these, but my work phone gets 2 or 3 a day from 0843 numbers on average.

You can block individual numbers using your phone's block-caller feature.