MT Enhanced Plugin: unauthorized error

Dear staff

MT Enhanced Plugin always throws the following error after working for less than 10 segments:

"An error has occurred while using the translation provider MT Enhanced using Microsof Translator: The request is not authorized because credentials are missing or invalid."

But if I open the project setting and close it without doing anything and back to the editor, the plugin can resume working.

Can you take a look into the problem?

thanks

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