Cartier Autoscaph is not automatic

My Cartier Autoscaph is not automatic!!! When worn on left arm is does not keep its reserve, when taken off at night it will stop. If the watch is fully wound manually and then left to automatic winding, it will keep going for four days (taken off each night) on the fifth moning it will have stopped!! The watch has been back to Cartier Belgium twice and Paris twice.. each time they say after checking that the reserve is 48 hours... I believe that the movement is at fault, that for some reason the automatic winding does not work. Recently the watch went back to Cartier again, where they replaced the movement with what they call a second generation movement (not a secondhand movement) at least I hope not! Although.... After a two week trial, the watch still stops after four days, HOWEVER if I wear it on my RIGHT arm it keeps going!!!!! In Belgium gear change is a right arm job, but even so are Cartier automatic only conceived for gear change arms??? Unfortunately the strap is most uncomfortable on this arm and of course my reflex is to look at the watchless left arm.
Anyone else having a similar problem????