$NIO(NIO.US)I bought 22nd calls, 5 contracts, but probably meaningless, the price is too high. So I should just give up exercising them, close the position. Why did the system email me today to pay attention to margin? The financing limit in the account may not be enough for exercising. Can't I just let them expire worthless if I give up exercising? I'm the buyer after all. Asking the experts, first time dealing with options.