You've now mentioned another PCN, JK17310112.
You say you have NTOs and charge certificates for both JK17310112 and JK17309044.
Your problem is that failing to act after service of an NTO leaves you no legal recourse. I presume you made no representations to Southwark for either of these?
All you can do is ask Southwark to consider late reps but you say:
I am also seeking confirmation of the current status of JK17309044 and JK17310112
But we know the status - both are showing online at charge certificate stage, £165 each.