Whatsapp Bulk Sender (Website)

I need to develop a website which allows me to do the following: 1. Send text messages, images, videos and files to WhatsApp 2. Allow users to register to the system but only the administrator to enable them and assign them a number of messages they can send 3. The system must validate the number of messages sent and discount or subtract the messages from the balance they currently have! 4. The system should have the capacity to send approximately 1 million messages per day. 5. The system will upload the numbers to the system using a text file 6. The system should allow generating a process report (In PDF, Excel or TXT format at the user's preference), that is, Example: Phone Number, Message, Date Process, Status (Delivered, Rejected or not was WhatsApp number). Only offer people who really have experience in that subject and have developed something similar, since the system worked with channels should provide the tool to get them if you are going to work with channels, since I do not know any other way. In the offer you must put the REAL value of the project and the development time. 25% will be paid to start, 25% when I show and I test the system, the remaining 50% when installed on my server!