Bad Service and Spamming

Since 16/01/2018, MTN have started spamming my phone with messages of subscribed services, which I have not subscribed for at all, the more I block and reply and forward SMS output/stop, the more messages are pushed through, I have sent 2 E-mails to get my number off their DATABASE, with no avail I am losing Airtime and data, as where in the past I used 1.5 GB to 2.0 GB Max per month, I am already on 4 GB for this month, MTN is not reacting to my complaint either in email, or in their FB messenger. I trust that I am able to, via Hello Peter, resolve the issue. Thanking you in advance for your time and help