This is my personal experience on using the same tool and how to not get banned while spamming:-
1.After getting a number,chat with some of your friends to increase trust level,you can do it with your own accounts as well.
2.What bans you is sending message to a number which is totally new for your contact.To avoid this,what you have to do is if you are sending 100 messages a day then those 100 contacts should be sent as a v-card by one of your contact.This will ensure that these contacts were referred by someone to send messages.
3.Don't start spamming immediately,give it a rest for a day or two which is needed badly.
4.Do not go above 50-100 messages a day in the initial 3-4 weeks minimum.Start with 20 messages a day and slowly increase.
5.Use whatsapp Business instead of the normal Whatsapp.
6.Have a good spintax for your message.
7.Split your bulk messages throughout the day for instant bulk spamming
8.For every 100 messages you send,have atleast 2-10 numbers that will guarantee reply to your message.
Use these tips and let me know if it works,I am sure it will definately work.