Charged R40 000 on 1st month after ordering

I ordered 4 rain sim cards for my business at R250 each oer month, they were delivered the next day and activated by the delivery guy which was good, but the following day I decided to check the usage on these sim cards, I saw they had placed a bill of R10 000 on each sim card as my bill for March 2021, and I only just purchased those sim cards and only used 2 of which i can bet i haven't used much data as we haven't given them to our staff as yet. I called their customer care, someone did answer and they checked and said that I had placed an order for 200gb that's why the costs is adding up to that 40k for the 4 sim cards, I told him no! I only ordered 4 sim cards that will cost me R250 per month each that's all, apparently the sales lady who sold me these sim cards from Rain had "done something wrong" as the sim cards should come with default 3gb with the option to remove it altogether. well I failed to remove the 200gb, Honestly people why would I choose to pay R40k for 4g internet that works 19hrs a day, when I could pay for 5G internet from another service provider who will even charge me less than that by far. I need Rain to fix this asap, I cant have you debit my card monthend for such amounts and complicate my life going up and down, rather you fix it now before we have legal problems.