Vodacom - Disgusting service

I have been trying to get Vodacom to load the company business cellphone onto debit order since august 2018. I followed their procedure for loading the said cellphone onto debit order on a company letter head with the Company CEO's details and sent off the letter on August the 1st 2018. to date the debit order has not been loaded. I continuously get calls email stating the account is in arrears, I normally just do the eft , when I call them they request that I send the same information again. Yesterday, 15/1/19, I get a demand letter stating the account is in arrears yet again