I'm assuming that this is the automatic CVT gearbox
these are very sensitive to the oil condition so the 1st thing to try is replace the oil with fresh
and its also worth checking the amount of voltage present on the battery as its also common to have issues with the battery sulfation which then results in the alternator overcharging and a battery voltage of 14+ volts ( with the engine running)
this results in issues with gearshift quality and general operation
do you still need help?
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