Hi All

Was wondering if someone could help answer my question.

What exactly is a plea?

I received a combined summons for unpaid credit card debt but i am going to file the notice of intention to defend as i dispute the amount claimed and iv actually been fighting for full statements for about 2 years with no luck and so last week the sherrif knocked on my door and yes i got the summons.
So what exactly is a plea and why should it be filed 20 days after the intention to defend is filed?