honda fit 2001

hie..my vehicle seem to be stuck in 2nd gear. its an automatic and when i drive it it takes of well with small shudders and the rev counter goes 5000 at 60km/h and when release the accelarator the revs stay that high for a couples of seconds then drop. No check lights on the dash. Diagonisis shows all clear. i have changed the ATF with the recommended CVT but no avail. A gearbox “expert” opened it up,serviced it and said the gearbox is fine(his words) but the problem hasnt gone away. Funny enough when i put it in drive whilst all wheels are suspended it seems to be ok as the speedo goes 120km/h at 3000rpm. please advise on what to do