I sent a bulk email to my contacts but there is no evidence it went out and no one appears to have received it

I sent a bulk email to my contacts but there is no evidence it went out and no one appears to have received it

Hi.

Does anyone know why this might have happened?  I sent an email using the 'Mass Email Contacts' function in the Contact module; sent the email using a template that was successfully tested on two individual contacts; and the system said/confirmed it was successful.

Does it take time for the emails to go out?  Am I being impatient?

Also, will it show up in my Zoho mail account as being Sent?

Any guidance or feedback will be welcome.

Thanks in advance for your help.

Matt