Automatic whats app message

Application where you schedule contacts and send mss of whatsapp automatically to the contacts scheduled: -For that I have excel sheets with the name last name / ID number / cell number -I also have printed bases with which I look for that through a Imgen (jpg) to excel in order to use this application. I am looking for a flexible application that can be added as time passes. With respect to the messages that are sent: I will have different databases where, for example, 1000 clients have to send certain information, the next week another new 1000 clients have to send another type of information. With that I look for the application to be very flexible to modify the message in my own way. The message should say example: Example Excel: GARCIA MARIA / DNI 25658445 / Cel 1535038745 -Example Message: "Hello Maria, my name is .. I contact you to inform you .... That is to say that the message is automatic But personalized