Bad billing service

Telkom debited me yesterday while the account is still under investigation for last months supposed bounced debit. Instead debiting for this month, they also debited last months debit in question while they are still investigating it because I did not receive any notification of it bouncing nor any alert from their side because I had money in account for most of the month for the debit to bounce. Contacted two of their agents whom failed to provide progress where I'd call they will say they will respond and dissappear with no response at all. Even the second agent looked into the matter and said there is no trail showing that I am fault therefore the penalty and missed payment will be rectified and disappeared just like that