The charge is due under the Care Act, even if the person is not keen or has never agreed to pay them. That is, the charges are due, if the person is availing themselves of the service. The upside of this is that the services cannot be cancelled just because the person is in debt or is refusing to pay – the duty to meet need is separate.
HOWEVER, the liability has to be enforced, and that can only be done through civil proceedings for which the liable party needs litigation capacity. That might be an obstacle in the way of actual debt recovery, because even an appointee, deputy or attorney does not have to be a person’s litigation friend if the debtor lacks the capacity to be made a defendant.
Your problem seems to be that you’re talking about a direct payment, and they are often legitimately paid net. So that means that whatever the charge is asserted to be, they just PAY the other element, the shortfall between the asserted charge and the full budget. That means you don’t get the chance to fight the charge, but that is your choice. If a council decides to pay net, you cannot actually stop them without a good reason, such that the person managing the payment is not able to access the person’s own money for charges, because they lack the authority to do so, for instance.
Q. Can a service user stop paying the difference of the new charge while disputing the amount which they cannot afford to pay?
If the charge is being disputed, and you stop paying the difference between the charge and the budget, the full amount that is supposed to be spent on the service will not be available to be spent. The council does not have a legal obligation to pay MORE whilst you pay less, unless you give them a very good reason – they could exercise a discretion or they could ignore you and then you could go to the Monitoring Officer.
So in this situation the only option is to challenge the charge. That would be either on the basis of failing to allow a housing disregard, a disability related expenditure disregard, or because you’ve been refused an unaffordability assertion on review or appeal.
At a more fundamental level, if you have an issue with the size of the budget in the first place, either because of the rate per hour or the hours said to be adequate to meet need, challenging that would make the package better value, quite possibly, because the budget can easily get bigger without the charge going up in most council’s systems.