In the event where you notice a double amount reflected in your recent donations, there's no need to panic.
This likely indicates participation in a 'matching' campaign. But what does that mean?
In a 'matching' campaign, a generous donor or organization commits to doubling every donated amount. When 'matching' is active in the system, you will only be charged the amount you selected, however the website will display a doubled amount.
If it is a matching-BOX campaign, the payment you will see after clicking 'Donate' will appear as follows:
After you choose the amount the matching will look like this: