How to reduce bitterness from hops?

The recipe I am using calls for (2.5 gallon batch) 0.5oz German Tradition for 45 minutes, 0.25oz for 15, and 0.125oz at flame out. I find the flavor to be a touch bitter for what I am shooting for. Any suggestions on which area of hop addition would be best to reduced or eliminate to mellow out the final flavor?

You could reduce the 45 minute addition or move it to 30 minutes to get less bitterness.

Thanks. I was thinking that bitter came from the longer hop exposure and that the flame out add was for volatile oils, which is more aroma. Thanks for the confirmation.