In all constitutional monarchies I know about the King/Queen has no power, but still has formal constitutional duties. Like signing laws which parliament agreed about upon. Only then the law can become active. Kings/Queens sign these laws always. (Else there would be a constitutional crisis.)

In Thailand the King has no power. But does anyone know if a Thai law can only become law if signed by the monarch? I assume that to be the case, it is pretty standard. If so, is this very ailing King still signing laws every day? I can't believe it to be honest. But this should mean there must be a Regent now in Thailand? But I never hear anything about that.