Mweb
No accounts department worse than MWEB in SA

I have an email address with MWEB which I've had for a decade, which, at R480 a year for an addresss is overpriced, but that's another matter.
My company will not, due to, pay any emailed invoice. They will only pay on a mailed hard copy. I have records of numerous items of correspondence with MWEB telling them that. They say they will mail it. I get shuttled around their accounts department, because they never do. Then they keeep sending mails cutting off the account, I phone and explain that they need to put the invoice in an envelope and post it. They say yes, they don't.
Cat and mouse game, my email keeps getting suspended, cannot win with these people. They are disinterested, inefficient and unapologetic.
If I didn't have such a long history - with a decade of email, and worldwide contacts, I would love to tell MWEB to put their email address where the sun don't shine. How can such inefficient companies remain in business?