Would this be possible - postbox notification

Hi all, I recently added an aqara door sensor to my letterbox, it works great and I’ve set up automation to notify me if it’s been opened.

I would like to have an entity on Lovelace if the letterbox has been triggered that day (post being delivered) and shows a message like ‘you have post!’ but for it to disappear if the letterbox is triggered again (ie I open it to get the mail).

Does anyone have an idea as to how I go about something like this, I can do normal automation, but this seems complicated!