Issues with sending email suddenly

[CWhite54]

Hi need some help pls.

A customer email we have regularly used is suddenly showing Bounce back yet when we we mail outside of Hubspot and bcc Hubspot code it appears OK. No problem with client server so must be an issue with Hubspot we believe?

Can anyone suggest a fix please?

[danmoyle]

@CWhite54 the answer will depend on the bounce reason. I'd suggest starting with this resource: Email bounce types then Send emails to contacts that previously bounced. 

If you know that an email address is valid, a user with Email permission can unbounce the contact to restore marketing email eligibility.

HubSpot note:

• You should only unbounce a contact if you've confirmed that the contact's email address is valid. Sending to invalid email addresses will have a negative impact on your sender reputation and can prevent you from successfully delivering email to your engaged contacts.
• HubSpot enforces a monthly limit on the total number of unbounces you can perform each month. You can unbounce up to 2% of the total contacts in your HubSpot account, with a minimum of 10 and a maximum of 1,000 unbounces per month. An individual contact can only be unbounced once.

Hope that helps!