First off what are you putting in the end of the line? I know, more super basic questions, but have to go their first. If it is not a long tapered mono leader as intended for that line then that may be the problem. Again, what fly are you using? Lines like this are not mean to turn over very heavy flies. Sorry to go there, but it is best get those questions out of the way.
Is the line itself not casting well or is it just that the leader isn’t turning over like you like? Those are two very different situations.
The aero heads are some of my favorite lines to cast. Let me assure you that if lined properly for a rod they virtually cast themselves so we should be able to figure this out. But yes, as mentioned above some experience will help as the longer you get the more precise you timing needs to be, and the more you mistakes will get magnified. What do you usually cast on that rod?
Still these lines are as easy casting as you get in their category. However, in spite of what the Beulah PR
says are NOT “midbelly” lines by any notion related to how that term has been used up to now, and especially at the light end of the spectrum like the one you mention are really shortish SHORT belly lines! As a reality check 44/12.5 = 3.5! Normally we would consider STARTING to call is a SHORT belly a about 4x. Honestly barely past a long scandi lenght - even on a shortish rod like yours. So a big jump in skill should not be required. It should really be just the first baby step past casting a scandi, and comfortable, so I’m not sure the “length” here is the real issue.
I know some people with those rods but have never cast one. Where is it on the 6/7 spectrum? I know I personally like the 510 gr on my 7wt.
The first thing I do to see if a new line matches a rod well is to do a bunch of switch casts. You can tell everything you need to know from that, and it might eliminate some other casting issues from the mix.