Bitcoin is the biggest reason behind the hardness of buying because the price of Bitcoin is gradually increasing.
Ya price is the one of the reason for hard to buy a Bitcoin.Now the price of bitcoin is around the value of 7700$.Before a 3 months the price of bitcoin is only 3000$.Many invested in bitcoin ,now it's double the value.It's the reason for reduce of bitcoin buying.But still you can inverse in bitcoin to get profit ,since the value will raised to 8000$+.