Thank you for contacting WPML Support. Could you please make sure your current site URL and registered site URL are same e.g. with www or without www.
If still issue persists, please follow the steps below and let me know how it goes?
- Again register WPML in your site and enter the new key:
Please Login to your WPML account >> go to Sites page >> Remove your current site / domain from there >> and re-add your site >> it will give you New key which you can add back in your site: https://wpml.org/account/sites/
Please let me know if this resolves your issue or you need further assistance with this issue.