RCM paid by CHA

I can't understand this one
" he raised transport invoice service and paid RCM himself "

he raised invoice and paid himself RCM...
what is this means?
bcoz, how can they paid RCM himself for their invoice...
It's not possible/correct.

So, as per this and Your query.
You want to pay GST under RCM basis for the CHA bill.

Certainly! Let’s break down the situation and address it step by step:

Custom House Agent (CHA) Services Invoice:
You engaged a Custom House Agent (CHA) for services related to customs clearance, documentation, and other customs-related activities.
The CHA raised an invoice for these services.
Transport Invoice and Reverse Charge Mechanism (RCM):
The CHA also incurred transport expenses while providing their services to you.
Instead of charging you directly for the transport services, the CHA paid for it themselves.
Later, they reimbursed themselves by including the transport charges in the invoice they raised for their services to you.
This situation falls under the Reverse Charge Mechanism (RCM).
RCM and Your Books:
In RCM, the recipient of the goods or services is liable to pay the tax directly to the government instead of the supplier.
Since the CHA has already paid the tax on the transport services (under RCM), you can claim this as an input tax credit (ITC) in your books.
You should book the RCM amount as an ITC in your accounting records.
GST Return Filing (GSTR-2B):
The RCM amount will be reflected in your GSTR-2B, which is an auto-populated return showing eligible ITC based on the details uploaded by your suppliers.
Ensure that you reconcile this information with your books and claim the ITC accordingly.

It means we paid RCM &take ITC in our books.
but cha is not a transporter ?