Programmers wanted! for mailing program -- 2

I try to send 5-10k emails every day through a third-party email service. I'm looking for developers with enough experience in third-party email services. For example, a month, I try to send 300k of mail at most using a mail service such as mailgun. Of course, we will have to pay for the money we need here. However, the problem is that our mail should not be treated as spam when we send e-mail under the condition that we are in charge of this financial burden. The mail should be delivered to the customers we need. This project doesn't matter on any platform. Developers who believe that this project can be done successfully are invited to participate. The price is 300$.