Repetitive call, by several different people, each...

Repetitive call, by several different people, each giving a different speech, giving only half the information
A contract has been signed without authorization from me, and when I call directly I am told that nothing can be done and that I simply have to send an email explaining the situation.

What is the point of having a customer service if nothing can be done for the said customer?

Telephone canvassing may be independent but ensure that it is of high quality and informative