Account Softlock can't be removed

I've been trying without much luck to get my monthly call limit increased by the Vodacom call centre. They are not very helpful and keep on telling me that it might take 1 hour, 24 hours and 72 hours for my request to be attended to. Why is it so difficult to increase my limit this month because I've been doing it for the last few months without any hassles. I've been given reference number S3-9J81D-DDW0M that does not get attended to. I'm really tired of speaking to their call center agents!