Bad service by M-sure

I am having a terrible headache because of M-sure. I lodged a complaint last week Wednesday and up to now it is not resolved. Instead of ensuring that the service provider is held accountable for a warranty on repairs done in December last year, they are giving me the runaround. From last week Monday I don't have a car, the service provider has confiscated it because they want me to pay for stripping which was neither authorized by myself nor M-sure. M-sure staff are supposed to be technically knowledgeable but they agree with the service provider on some stupid theory and are trying to convince me to accede to the service provider's demands which are ******** and unreasonable. In this matter, clearly M-sure is protecting the interest of an ************ service provider who thinks he is above the law, yet I am paying M-sure every month. Clearly M-sure staff are colluding with service providers to rip us off.