email cant send out

email cant send out, error message say:

[The email could not be sent due to a technical issue with PHPMail: The email could not be sent: Could not instantiate mail function.

Please check your sending method configuration, you may need to consult with your hosting company.]

Sending has been paused due to a technical issue with PHPMail: Could not instantiate mail function. Unprocessed subscriber: (Chuah YM YM <xxx@gmail.com>)

Please check your sending method configuration, you may need to consult with your hosting company.

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