747 Not Descending

[Ryan Lorefice 0]

I was flying from Dubai to Heathrow and was preparing to descend, i put 16000ft into the Altitude selector and waited till T/D. as soon as i got to T/D i clicked on hold so that the place would descend but it didnt. It just stayed at 36000ft. I tried using the V/S Selector then pressing Altitude hold again but every time i did that the plane would just level off. Whats going on 

[achutchison 26]

That’s exactly what altitude hold does... it holds your attitude. You need to remain in vnav, vs, or flight level change to descend.

[downscc 1,327]

You really should fly the tutorial.

[30K 72]

Your kidding please tell me you are o.O