2011 BMW 128i automatic , when I go into semi auto on the transmission selecter I can down shift like normal but my upshifts will get over ridden by the computer almost immediately Making it Impossible to stay in any gear longer than a few seconds. It's not throwing any error codes and just started doing that

those are endless money pits as they age. ONLY a pro bmw mechanic with a dealer scan tool can analyze and repair such a fault.. PRAY it just needs reprogramming, but only a bmw pro can do that.