Currently I faced one strange issue. I have integrated authorize.net credit card payment in my client website. A standard one not the ARB or CIM.

Last week few customer reported than after the one successful payment after 2 days their cc charged again.

So they faced double payment issue. 

I have not written any code or cron where we will re call the process. Neither we are storing cc details of customer. 

But still this issue exists.

Any idea why this is happening?