Unmentioned extra debit return charge

Good day, I took a contract with Telkom via DSL. I advised that I want a debit order to go on 25th. There was issues with my salary and only realised after 25th that my debit order did not go.

I immediately made a payment on the 1st on their websit but now this month they are charging me R210 extra as a debit order return note.Haybo! I read the contract by DSL and there is no mention of this on the contract note. Can Telkom please refund me back?