mass dms send

I'm looking for a freelancer to help me with a project - mass DMs send. I want to use Instagram as the platform for sending these mass direct messages, and the primary purpose of this project is to promote a product/service. The target is quite large - I'm planning to reach 1M people with the mass DMs. I'm looking for a professional with experience who has a bot in this field who can ensure that the task is completed smoothly.