My Mail keeps getting blocked

[HB9]

THIS IS FOR HELP WITH A MAIL SENT BY GMAIL, I guessed you guys could help, scince google doesnt help...

I just created an email address for my school class (to send information to parents), and it has now bounced for the 3rd time the email i've tried to send. Yes, it is coded, but I sent it from my personal email and it worked. So I then tried to make a group with all the contacts, I did it and it still is not working, I checked and all the email address are well written too.

 

Please help.

 THIS IS THE MAIL>

Promoción graduanda del 2018 del Colegio Luis Muñoz Rivera View this email in your browser

PROMO 2018

Consejo Estudiantil Este correo es enviado en representación del Consejo Estudiantíl de la promoción graduanda del 2018. Colgio Luis Muñoz Rivera /////////////////@gmail.com /Febrero/14/2017   Nuevo Correo Electronico Estimados padres, madres y tutores, Se les extiende un cordial saludo departe del Consejo Estudiantil, para agradecerles a todos por su devoción en ayudarnos con nuestra promoción.   Se les envía la presente para informarles que gracias a sugerencias de los padres, el Consejo Estudiantil ha creado su propio correo electrónico (/////////////////@gmail.com). A través de este se realizarán las comunicaciones entre el Consejo Estudiantil y los padres/tutores.   Muchas Gracias y Felíz Día de San Valentín. - //////////////////////////////////// Presidente del Consejo Estudiantil

THIS IS THE MESSAGE I GET WHEN I SEND IT>

Message blocked Your message has been blocked by /////////////////@hotmail.com. See technical details below for more information. LEARN MORE

The response from the remote server was: Message rejected. See https://support.google.com/mail/answer/69585 for more information.

Final-Recipient: rfc822; /////////////////@hotmail.com
Action: failed
Status: 5.0.0
Diagnostic-Code: smtp; Message rejected.  See https://support.google.com/mail/answer/69585 for more information.
Last-Attempt-Date: Tue, 14 Feb 2017 12:10:38 -0800 (PST)

[demonix00]

Are both accounts gmail, because if they aren't then it's highly likely that the recipient has blocked either that account or gmail in general.