This thread is resolved. Here is a description of the problem and solution.
Problem:
The client has installed the WPML plugin and generated a key after purchasing a license, but the plugin was already installed and activated with a different key.
Solution:
If you're experiencing this issue, we recommend that you generate a new WPML key for your domain by visiting https://wpml.org/account/sites. After generating the new key, copy it, then navigate to your site's backend under Plugins > Add New > Commercial. Here, unregister WPML from the old key and then re-register it using the new key. Additionally, ask the person with the other account to remove the old key from their WPML.org account as it is no longer needed.
This solution might be irrelevant if it's outdated or not applicable to your case.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 at WPML support forum.
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