This thread is resolved. Here is a description of the problem and solution.
Problem:
After moving the site to a new hosting provider, the client encountered an error stating 'WPML plugin cannot connect to wpml.org' due to a site key mismatch.
Solution:
If you're experiencing this issue, we recommend you follow these steps:
1) Ensure you have a full backup of your site.
2) Navigate to your Site Dashboard, go to Plugins>>Add New>>Commercial.
3) Click on the Unregister WPML from this site button.
4) Visit WPML.org, go to My Accounts>>Sites, and delete the existing site key.
5) Create a new subscription key for your site
6) Return to your Site Dashboard, go to Plugins>>Add New>>Commercial, and register with the new site key.
7) Refresh the page.
For more detailed instructions, please check these tutorials:
https://wpml.org/faq/wpml-plugin-cannot-connect-to-wpml-org/
https://wpml.org/faq/troubleshooting-registration/
If this solution does not apply to your case, or if it seems outdated, we highly recommend checking related known issues at https://wpml.org/known-issues/, verifying the version of the permanent fix, and confirming that you have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 further assistance is needed, please open a new support ticket at WPML support forum.
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