Exercise logging 2 weights should respect available weights

For some exercises the total weight and not the weight of one dumb bell is logged. It would be great if the app would suggest weights that are acutally possible by combining the weights I configured. Say I have two dumb bells for 1, 3 kg each available. Now would happens is, after I trained with 2kg (1+1) the app suggests 3kg. That's not possible with my configuration. The next possible increase would be 6kg.