Whether, since the implementation of the Gauteng e-tolling system in December 2013, this system or part of it (a) were not functioning or (b) malfunctioned; if so, (i) on which date(s) the system of parts of the system (aa) were not functioning or (bb) malfunctioned, (ii) which parts or sections of the system were faulty in each case, (iii) on which overhead gantreys this had an effect and (iv) how long the problem or problems persisted?