Telkom billing system sucks

Telkom is the worst ever, my wife app**** for adsl (R199 promo) in February as fiber was not live in our area yet she was told that once fiber was live she could migrate to fiber at no additional cost. Well 2 months ago fiber became live and she app**** for the migration (R399 promo) , everything went well fiber was installed and bam she received a statement with of over R600 went in to a telkom direct and they asserted her saying that she will be credited the extra amount deducted. We thought it was resolved and bam another statement for R949. We are ready fed up with this nonsense someone needs to do there job correctly as this can not carry on