Cancelled contract but still deducted, ******* brand

Mtn mall of the south they just hired a bunch of ******* people, I took a home internet but they August due to poor network I had to keep calling I ended up returning the route at the mtn mall of the south, I gave it to Irene the lady with specs she was so rude and not even willing to help, she did not cancel the contract now they took money on my account I went back to the shop they said I can’t get a refund and refused to assist me, the other 2 ladies were busy giggling the shop was so full no one was willing to help I went back home without help. Mtn should really look into this customer service matter otherwise u will lose customers such a big brand full of useless people !!