Notice Flush/add to Cache

[CoffeeLovesYou]

Hello,
I made a notice creator form that will easily create notices for my staff (with no HTML involved for them).
Basically, it's a HTML form that they enter the info, and it makes it into HTML for them (e.g. if they put Color #FF0000, when I pass it through the query to add the notice's phrase, it'll do <font color="#FF0000">).
I'm not comfortable sharing my code publicly, however, it works. It adds the notice to the notice table correctly, the noticecriteria table correctly, and the phrase table correctly.
Here's the problem. Notices are cached. The cache isn't flushed unless you add a notice from the ACP or modify one.

How can I flush the cache when adding a notice from my form? Or how can I add the notice they just made with my form to the cache? (whichever one is the right one).

Thanks for any help. If someone wants to help privately, I don't mind sending my code.