My wife saw this on a sign in a high-school attendance office.

Problem:
The verb is a horrible corruption of a good one.

Explanation:
The sign directed visitors in the office to not congregate there.

You might have to say this aloud a few times to get it.

The sign writer meant “mingling” when she wrote “mingaling” instead.

I believe that the writer hears three syllables when she or others (mis)pronounce the correct verb.

So she spelled it phonetically and got “mingaling” — hilarious, if it weren’t so sad!

Solution:
“Mingling”