Hi,
Now, I see a number of JS errors in the console log:
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The error which is most likely the cause of the stalling checkout is the 500 Server Error, this is pretty common in WordPress.
Please open your wp-config.php
file and add this: define('WP_MEMORY_LIMIT', '256M');
or if you have this with a lower value, increase it to 256M
.
Thanks.