I am using PHP cURL to generate new address from coinbase. As per this documentation we get notification on the callback url when any transaction is made on the generated address. But I am not getting any callback from coinbase when I receive any payment.

I want to achieve the following:

1. Generate a bitcoin address

2. Store the the generated address & the amount with it's user who paid it.

I am facing the problem in getting callback. I get payment in the coinbase & email saying that you received this amount etc., but no callbacks.

Also please suggest me that whether the coinbase is secure or not. If not, what should I go for? I want to get the above things done.