Shortcode not working

The shortcode [wcj_order_number] is not working when I try to add it to the “Order received” Message Options. I have had this custom message working fine for 2 years. Why did it suddenly stop working?

<h2><strong>Congratulations! Your registration is successful. ??</strong></h2>
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<p><strong>Your Order Number [wcj_order_number] is your unique Registration ID.</strong></p>

<p>Kindly save this page for your reference. You'll need your Registration ID for submission. The same details have also been sent to your billing e-mail address.</p>

<p>If you can't find the email in your inbox, please check your spam folder. If you have any queries, you may email us at <a href="mailto:[email protected]">[email protected]</a> with your Registration ID and the Competition name as the subject.</p>

<p><strong>Good Luck!</strong></p>
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I have also had issues with the “Prices and Currencies by Country” module. So I had to disable all price and currency modules as I was losing sales. I’ve had that working fine for the past 2 years as well.

Why did Booster suddenly start having problems?

The page I need help with: [log in to see the link]