Hi Vince,
Actually, you're one of the lucky group of people who have a phone where the charging port is mounted on a circuit board that's separate from the motherboard. That means the port can be repaired fairly easily with no soldering required - something that's particularly difficult with USB-C ports.
I have to give kudos to Lenovo for making their service manual public; that means you have factory specific repair procedures to go by to fix your phone. Here's the one you'll need for replacing your charging port/sub board.
[document|35887|ThinkPhone Level 2 Repair Manual - iFixit]
The sub board replacement procedure is on page 120, but you'll need to follow the previous pages to get to it.
The part itself seems to be available practically nowhere; it's complicated by the fact that the service manual doesn't have any part number information. However, I did manage to locate a couple of places you can buy it; I'd definitely go with the first if possible since it's quite inexpensive and a brand new OEM part, while the other is used and inordinately expensive for what it is.
[link|https://www.wholesalegadgetparts.com/charge-port-board-for-motorola-thinkphone-genuine-oem.html|Charge Port Board for Motorola ThinkPhone [Genuine OEM] (Closeout) - Wholesale Gadget Parts]
[link|https://www.ebay.com/itm/135519928708|OEM Motorola ThinkPhone XT2309-3 Charging Port Charger Plug PCB OEM - eBay]
Of course, if you do your own search you may find more options if neither of these works for you.