There's quite a bit missing from your account so I'll make a few guesses.
Does this relate to a speeding offence? And was the "PCN" a Conditional Offer of a Fixed Penalty?
If so, and you now have a "court summons" (which I suspect may be a "Single Justice Procedure Notice") the fixed penalty procedure is dead and buried and you can no longer take advantage of it. So "Part 2" of whatever it is you have posted up is no longer of any concern to you.
Instead you are now being prosecuted in the Magistrates' Court for the original offence. Let us know if my assumptions are correct and we can advise you how to proceed.