I used the instant buy feature a few times, I had no problems and it was instant.
Same with me, until the past 2 days. Previously my instant transfers went through fine. Now they don't go through at all
I'm guessing the "high risk" BS message is a cover-up for the fact that coinbase doesn't want to sell their coins at a loss. I'm guessing they bought them high and obviously don't want to sell them low. So instead of saying that, they just say "it's high risk". They don't want to lose money.
I have defended coinbase in the past thinking it was just a fluke or user error like NSF (I had one of those)..
I have instant buy, I have done 10's of thousands in transfers with them. Today I try instant buy for 1.8 measly BTC and get the cancelled because it looks risky. WTF! As stated by others I bought 10 BTC at 900/usd, It was higher than that, they didnt hesitate to take 9800.00 from my bank account and give me the coins.
Dont be to sure they dont pull from your account because it was cancelled. My notice had this in it. Even though it went against my instant buy amount and was cancelled. Instant buy shows I can buy 8.2 now instead of 10 even though they cancelled it.
Unfortunately, we have decided to cancel this order because it appears to be high risk. We do not send out any bitcoins on high risk transactions, and you will receive a refund to your bank account in 3-4 business days.
If they continue to be Jack asses like this, I will be out of business. Growing pains I guess.
I will keep this thread updated however it washes.
Best of Luck.
Exact same thing is happening to me now and I have bought from coinbase successfully many times in the past as well. Don't worry, they didn't actually charge your bank account. I checked mine several times to make sure. It's just some pre-made message they send out because they don't want to sell bitcoins right now at a loss to them (this is my best guess).