Problem: The client wants to change the hreflang tags generated by WPML from hreflang="zh-hans" to hreflang="zh-my" and hreflang="en" to hreflang="en-my". Solution: If you're experiencing this issue, we recommend you try editing the hreflang tags by navigating to WPML > Languages > Edit languages. Here, you will find a column where you can change the hreflang attribute for each language.
This solution might be irrelevant if it's outdated or not applicable to your case. We highly recommend checking related known issues at https://wpml.org/known-issues/, verifying the version of the permanent fix, and confirming that you have installed the latest versions of themes and plugins. If the issue persists, please open a new support ticket.