Shimano calls for three steps on their manual to adjust the FD
1) Set the chain on the smallest chainring and the largest sprocket and adjust the low stop
2) Set the chain on the largest chainring and the smallest sprocket and adjust the high stop

These two steps I had no problems with, the third step is the top position electrical adjustment, the chain goes on the largest chainring and the largest sprocket, then using the electronic adjustment I'm supposed to adjust the derailleur to where there is only 0-5mm between the inner plate and the chain, the problem here is I'm running out of adjustment and still have 2 or 3 mm to go

I checked my crank and is centered, also the FD is properly aligned to the chain line. I can get the chain to shift to the largest chainring in manual mode if I'm on any of the smaller three sprockets; but if I use the synchro shift or manually shift when on the larger sprockets (6-7-8) I can't get the chain on the larger chainring. Any suggestions?