W221 transmission cuts out

Hi, i recently changed the transmission oil and all shifting solenoids in my 722.9 box after it just started slipping,

filled the transmission with the right red oil from benz, about 9 litres and dropped the excess amount at 45C degree.

after the oil change the car drove normal for a week, after a week the box started to cut out while driving as if it goes into neutral and then back in gear. the next morning it would not go, when you put it in gear, it rolls with no power, just enough to roll on flat ground (same with reverse), if you hit the accelerator the engine revs but the car does not move. i suspected the transmission pump because the transmission has no energy in it, but i am doubting it because there is no noising coming when i rev the engine. i am scanning it with Autel Maxicom MK808 scanner, no faults are showing for the tranny. what could it be?