First time i posted him for 12mil then 11.5 then 11 and so on i've had him on AH for about 3 days now and i've lowered the price on 8.5 mil and still nothing. The cheapest on the AH now is 13mil.
It doesn't matter what's on the AH if there's no bids. You need to find a price at which the card is actually selling to sell yours. The bot will list your card as long as you're not above the cap for a given OVR. The reality is that the AI cards have been showing up more frequently as of late (especially NBA version due to Harden) so the price is dropping.