Always a good idea to
#1-post the version of Inventor you are using (many of us like to include our Inventor version and even computer hardware in our signatures so its always there)
#2-post the Inventor files
#3-if you can't post the files due to "company secret" info then see if you can post a non secret file that exhibits teh same behavior.
#4-if you can't do 2 or 3 at least post a screenshot showing the problem.
... having read "similarish" issues on the forum.
1. Sketch 1 is not fully constrained (not even 1 dimension). You need a horizontal and vertical construction line. Notice that the sketch points can be dragged anywhere (one of them even off of the ellipse).
After fixing this problem do a Manage>Rebuild All - notice the "sick" sketches. As a beginner, I recommend that you simply start over rather than getting into what it takes to fix a sick sketch (not that it is hard to fix these two, but as a beginner you need to learn to avoid creating sick sketches altogether - so start over).
2. You were using the wrong Loft settings (use Rails, not Centerline).
3. You will need to either trim the rails and mirror or create two more profiles at 90° - I recommend the second option as mirror of a loft doesn't always give you the correct geometry.
Attach your second attempt here.
Sorry for the non constrained sketch (I do have some idea of constraints but was seeing if that itself was an issue with the loft not following the rail/s).
I have attached a second attempt which I believe to be fully constrained, I have added a sketch at 90deg as you suggested but still no luck with a loft following 2 rails. I have also tried to introduce a third sketch at 45deg but for some reason when I construct it as I did the others the intersections of the projected geometry end slightly past where I need them to be?
I have tried using the rails rather then center line but it isn't working, the closest thing i can get is an area loft but even this isn't following the rails. offsetting one of the ellipses to use as a rail doesn't work either as they differ in thickness still in areas :-/.
Thank you very much for the help you are giving me.
I would try trimming the ellipse.
When you say trim the ellipse do you mean the parts beyond the profiles I am trying to loft?
I have attached an image of what I mean, the green being what I do not trim.