You can report nuisance calls and spam texts to the ICO here.
Report spam texts or report cold calls – that either played a recorded voice or were from a real person – to us and help us stop nuisance marketing messages.
We will use the information you provide to help us investigate and take action against those responsible. We don't respond to concerns individually.
You don't have to answer all the questions we're about to ask you, but please give us as much information as you can. The more evidence we can gather, the more power we have to take action against those making nuisance calls or sending Spam text messages.
Source: https://ico.org.uk/make-a-complaint/nuisance-calls-and-messages/