The amounts have been corrected for my card and I have been advised to not use Curve cash where currency conversion is needed until the matter has been fixed.
This is a part of the support response:
Thanks for getting in touch and I’m sorry for the delay in getting back to you. We’re currently receiving a high volume of messages which means we’re unable to respond to you as quickly as we’d like.
We have had an error that has caused incorrect exchange rates when using Curve cash. This started around 10/10 and we are still working on correcting it.
I have refunded all of the incorrect payments and you will see the balance reflected on your Curve Cash card. Whilst we are working on getting this fixed we would advise not using the Curve Cash card for transactions that require an exchange.
I am not sure when currency conversion is used so I guess I will just not use Curve until it has been fixed.