Imagine you’re a busy exporter who accidentally issued the same PI number for two orders to the same client, say ABC003. The client noticed while making payments and smartly added ABC003 XXX and ABC003 YYY in the remarks to differentiate. Checking the bank slip, you realize the first order has already shipped, and the PI number can’t be changed. You quickly update the second order’s PI to ABC003-YYY. Now you’re worried: Could this cause trouble for the client?

Don’t stress! The client’s differentiation in payment shows they’re detail-oriented and cooperative. As long as their accounting team can distinguish the payments and customs documents match, there shouldn’t be major issues. The key is ensuring all documents for the second order—like the commercial invoice and customs declaration—use ABC003-YYY consistently, so the client receives clear, matching paperwork.

This is straightforward. Since the second order’s PI is now ABC003-YYY, the commercial invoice’s contract field must also show ABC003-YYY. Why? Because consistency in international trade documents is king! Mismatched numbers from PI to invoice to bill of lading could raise customs flags or confuse the client. So, no hesitation—write ABC003-YYY for clean, clear documentation.

My advice: Proactively inform the client and send the updated PI. Since they’ve already helped differentiate the orders in payment, they’re clearly cooperative. Sending a new PI shows professionalism and prevents future disputes. A simple email like, We noticed the repeated PI number and have updated the second order to ABC003-YYY for clarity. Attached is the revised PI for your reference, is polite and efficient.

As for refunds and re-payment? Unlikely. The client has already paid, and the order is in progress. A refund would be cumbersome for both sides. As long as subsequent documents are correct, they probably won’t go that route.

Honestly, repeated PI numbers aren’t rare in exports. Some peers handle it by adding -001 or -002 to the PI number or generating a new one entirely. As long as the client and bank can match payments with orders, and goods align with documents, business proceeds smoothly. As one veteran put it, If the client already differentiated, it’s fine. Consider this a minor lesson!

A repeated PI number is a small hiccup, but it’s a reminder: In exports, every digit in documentation matters. From PI to commercial invoice to customs, attention to detail is non-negotiable. This time, the client helped smooth things over—don’t count on luck next time. Double-check PI numbers to avoid small oversights derailing big deals!