If you are getting “Failed to send your message. Please try again later or contact administrator by other way.” error message in your contact form then you are using Contact Form 7.
To solve this error in your contact form 7
1.Login to wp-admin. In your admin dashboard click Contact.
2.In your mail settings change the From field to email belongs to your domain.
Example: [email protected]_domain.com
3.Save the setting and test your contact form.