After a long time bitcoin gone under 10000$

and crypto market down also.What is the main cause? bitcoin ban facebook ad or other option ??
Corrupted government is the only reason for this situation but don't worry this situation won't last for long. They are already realizing the inevitable; that the merge must happen. Price will go up and the HOLDERS will be satisfied with the events that are being put in motion.
This current value of BTC is just a standby phase in which you must not allow your panic to prevail!