citroen c4 grand picasso exclusive plus creaking rear suspension

hi bought 63 plate with 20000 milage, citroen c4 gp exlusive plus from a citroen dealer, and after few weeks i noticed creaking noise from rear axle, i booked to check whats wrong with it, so citroen dealer said, the citroen know about that fault but, they cant do nothing because they trying found solution, and then they diagnose solution they give me a ring to fix it, but they don't know when, can someone help me its very bad noise, what shell i do, i cant drive with creaking noise for a year or two, its 63 plate car by now they should know how to fix this problem. Does anyone have same problem?

Any advises guys

Thanks