[Matthew]

Numbers get marked like this when people report them as spam, often by mistake but unless you recognise a number or are expecting a call back your not going to answer it unless you are 1 of these that answers all calls. Numbers mistakenly get tagged then and not always as each to remove or it could be part of a batch of numbers that are used for spam. If you are not expeciting a call or they cannot verify who they are end the call simple.