If you are short you have to put up more and more collateral as the price goes up. So yes, eventually you may be forced to buy to cover your short, if don't hav

If you are short you have to put up more and more collateral as the price goes up. So yes, eventually you may be forced to buy to cover your short, if don't have enough cash you are able or willing to tie up as collateral. This can create a feedback loop as short-sellers buy and drive the price further up, forcing other short-sellers to buy, etc., the so-called short squeeze. I have no idea if this is happening now.