Online Tax Renewal - Distance Selling?

[willibetz]

Is online tax renewal subject to distance selling regulations?

I ask having today applied for a six month tax disc, intended to cover use of a second car from May to October. Having belatedly checked, I now realise that the disc will be issued effective from April.

I've tried to amend the application via the related call centre, but this appears to employ empathetically challenged individuals capable only of repeating the mantra that the transaction has been completed, is non-refundable, cannot be amended and there's nothing anybody can do now...

It's undoubtedly my fault, but it seems ridiculous that the application can't be amended or voided. As I can't correct the mistake simply, I now wonder whether I have recourse under a cooling off period?

Thanks in advance...

WilliBetz