To add to what others have said I had similar situation with a flow hive which took over six months fir the bees to take any interest in the flow frames…they spent a lot of time wandering g around them but it was only after I put some traditional frames in with the flow frames that they started building, out the traditional wooden frames and once they were built out and full of honey did they continue on filling the flow frames…but in the end they didand its now being capped off so im looking firward to my firsy harvest soon. Like many others I was concerned that the flow frames were a flop for me but it was all a matter of patience and they got there in the end.
In the meantime I bought a second flow hive and once the brood box was at a point where the flow frames could be put on…I heeded all the hints by Flow and others and prepared the flow frames first. I washed them thoroughly to remove any possible manufacturing contaminants, then melted beeswax and used a foam paint roller to roll on a layer of beeswax on both sides of all flow frames and then used a spray bottle filled with sugar water mixture and sprayed a layer all over both sides of the frames.
That was only done a couple of weeks ago and I’m not expecting the bees to start filling the flow frames yet but the numbers of bees all over the flow frames is promising. So from a newbie Beek who was starting to doubt the flow system my lesson learnt is that the number 1 rule in bee keeping with flow hives is patience. 