Are you talking about the Dual Tax Agreement between Turkey and the UK? If so, you have to apply to the UK tax office to be declared Non Resident. You have to prove yourself permanently resident in Turkey, by providing your stamped and verified Turkish Tax Card, last UK Tax Coding, Resident Permit, and several other documents that I can't remember. Once you are declared non resident in the U.K., you can only stay in the U.K. for so many days in a year - 90 I believe? The forms can be downloaded, and it takes several months for the process to be completed.
A Resident Permit on its own does NOT remove your U.K. tax liability.
Other than from the government tax office itself, you could not get a clearer answer. You have already done that, but if your request was in English, and not in Turkish, you may not get any reply, unfortunately.