TELKOM INCORRECT DEBIT ORDER DATE

I app**** for a ADSL line with Telkom Bluff Store in Durban in November 2018. I requested for the debit order of R605.00 to go off on the 20th of every month. Since December and January Telkom has been debiting my account on the 5th of every month. I have been calling the call centre from December, January and yes again in February. A call centre agent told me in January that the amount of R605.00 will be debited on the 20th February. I had not expected a debit of R605.00 to be taken off my account last night. I again called Telkom this morning and was told by the Manager Nosipho that the system can only be updated after 3 months. Why wasn't i given this information all the other times i called, i would have been preparted for Telkoms debit order. TELKOM HAS ROTTEN SERVICE OVERALL AND THEIR AGENTS ARE NOT CLUED UP ON HOW THEIR SYSTEMS WORK, INCLUDING TELKOM BLUFF BRANCH WHO PUT THE INCORRECT DEBIT DATE TO BEGIN WITH.