papia.. please follow the suggestions provided. If there is a business need , go for a commercial solution as for now there is no guarantee your e-mails reach the recipient. The issue is , like stated a few times with the reputation of your IP (hosting providers ip). As i noticed a entry of your ip on a blacklist vanishing , i suggested to wait and try again later. Big providers cache information so it can take some hours for them to receive the delisting. But you have not tried. Did you look into the google postmaster tools as suggested ? I don’t think so.. you keep posting.
Please, if you want help, follow suggestions provided above by everyone replying. There is no magical button to push and solve your issue unfortunately. Even if you pay mailcow to help setup your server they can not , i repeat can not force google to accept your e-mail.
I only can repeat what has been said before.