I wouldn't worry about this. It is OTC  and it shows how shallow the market for them is. Overall, the markets are really shaken today with the new COVID variant and everyone is running to safety which, of course, neither ZCC or RVX is. The buyers have pulled out of this risk and somone panicked and gave some shares away for nothing.It was only a handful of shares. Let the world markets settle down and it will probably return to about where it was. How low the price was OTC to begin with shows how vulnerable those shares are. There is an extra risk factor added to them there.