Lying

What would you do if you ask your husband about some payments he’s made and he just lies right to your face? I already seen and knew about the payments he made and then I asked him if he’s made any payments concerning what he’s paying for and he just lies straight to my face and then i asked him if he’s sure and he says he’s positive. I asked him again this time telling him how much he’s paid on them and he just looks at me and just walks away knowing he got caught in a lie. I don’t understand how he finds it so easy to just lie straight to my face :(