They calling 2 times a day, asking for my sister,when i am saying he is not here and  where they are calling from??, just hang up.

They calling 2 times a day, asking for my sister,when i am asking she is not here and  where they are calling from??, just hang up.

This number keeps calling and asking for my  husband and won't discuss anything further when I say he's not availlable and just hangs up. It's really bothering me.