very much agree with both points here
Maybe the OP can have a go at doing a basic draft of a letter / E-Mail to Transport Focus that we can then help bash into shape to be sent off - time is of the essence here so this is the next step and needs to be down ASAP.
The clock is ticking on when the payment is due -
and if not paid soon the OP will lose the ability to benefit from the £50 discount in payment I assumer - which is why I have advocated to
@kyaadam that they need to be paying it whilst we then help with the draft to Transport Focus in the hope that the sum paid will eventually get refunded.