Double debit unknowingly

I went through my back statements and realized, that the payments deducted from cartrack are not consistent. Sometimes it’s double other times its added with R50. On top off that all sometimes they deduct on date that was not agreed upon. Leaving me to pay the service fees. I only got a 3 months bank statement and was shocked. I just wonder how far back this has been the case. Sent them an email attached with my back statement. No efforts were made what’s so ever to resolve the issue.