A. If you saved the screenshot to Cloud (Awesomescreenshot.com), please follow these steps to remove it.
1. Log in to your account and locate the item. Usually, it is listed under My Items.
2. Hover your mouse cursor over the item's thumbnail and click on the "..." icon.
3. Select Remove to delete the item from the menu that appears.
B. If you saved the screenshot to Local (your computer), the captured screenshot is temporarily saved in your browser.
If you choose the 'Local' saving option but do download the screenshot, enable "Auto-download screenshots", or set a cloud storage location in Options, the screenshot will be automatically deleted when you close the tab.
Related instruction: How to move or remove screenshots and videos in bulk