For checking status of credit card of HDFC, there are two options, one is to register yourself for getting online credit card statement status in your net banking. For this, you have to give the request application and give its reference no. and your mobile no. and your date of birth. You can also register online. Through filling the form by just going your HDFC website.
After this, you can see your monthly status of your credit card. You can also see past six months' credit card statements.
Second option is so easy and you need not to register yourself. You just login your net banking account of your HDFC. In your saving account summary of month, you will total withdrawal of your credit card. It will write like "CC your credit card no. autopay SI -TAD. In my case, it is showing withdrawal of Rs. 3555.23. Now, verify this amount with your credit card statement which you will get on your mail address. It will show where you have pay this 3555.23. It will also show you the online service or product providing companies name who deduct their payment. In my case both my total auto-pay has verify with my credit card statement. So, dual check is good for confirm the amount which is deducted from your saving account.
If it does not match, just call the customer care of HDFC immediately.