Unacceptable treatment by rain

A few years back I took out a 4G product witb rain it was stll back when you just lunch your 4G product i think ot was R249 can't remember correctly the 4G network was horrble so I cancelled tye product now that i wanna sign up for 5G I'm hit with a outstanding Amount of R278 for that old 4G product that I could never make ues of because the network was so slow now rain except me to pay for a product that was canceled due to slow speed a few years back unacceptable I'm.not paying for a product o had to cancel because I couldn't ues if rain can't remove that fee then I'll never do business with you and get MTN 5G then this is unacceptable