Set up a WhatsApp mass messaging campaign with official BSP

We are a non-profit with a list of subscribers in Palestine, Jordan, Lebanon and other countries. We are looking to partner with an official Whatsapp BSP to be able to send such promotional messages. We need someone to set the whole thing up for us. We don't want to do anything technical, just upload our list of contacts, type a message and send.

If this is something you can do, please start your message with lgl and tell me which partner you're considering. Please do not propose alternative solutions.