PAYJUSTNOW extra fees

I received messages that my PAYJUST NOW PAYMENTs FAILED 2 days in a row. One CANNOT phone them. I sent an e-mail that was not read and then sent another which came back with an answer that now I had to make payment AND there is a fee of R145 for non-payment. My Card details on my profile are correct and funds are available. There were no such transactions attempted on my bank account. Seems to me they are out to collect an extra R145.00 from their customers since they do not charge interest!!!!