know someone what happened? 
Unfortunately, it is indeed falling at this moment and that is probably caused by the cancellation of the segwit2x that was supposed to happen th month. But we should not be worried about it but rather take advantage of the backdrop and invest to Bitcoin. It woll eventually increase just like what usually happens whenever its market value is falling. I don't have a strong basis, but I think because of the cancellation of the upcoming fork, many investors decided to invests in altcoins, causing for BTC to drop. Anyways, the drop didn't happen long enough, after hours it is rapidly recovering. No worries, bitcoin will still bounce back whatever happens. Don't panic too much, if you see a btc drop, then use the chance to buy some while the price is too low.