Zulzi payment methods

They have always delivered my shopping on time and I have given them a few chances but will not use them again. Firstly they deduct the amount from your credit card immediately and then do the shop. With my last shop they debited my card for R500 and credited my account for R85.00 but the actual slip from woolworths was R261.00 (Inv. 306571). Even if you add on the R90 delivery and service fee, there is a shortfall to me. I reported this and sent the slips and original order but it has not been resolved. This has happened before and I think I was done out of about R200 but I was extremely busy and never got to report it. Surely they should only debit your credit card once they have completed the shop.