Issue with repeat structure

Hi,

I am having an issue with some repeats that I can't get to function the way I want them to. Here's the issue:

In my piece, the first section of the piece is broken down into two little phrases. I want each one to repeat once before moving onto the next thing. After the second repeat of the second phrase, there is a short transition section that either transitions the piece back to the beginning or into the next section. I was trying to accomplish this with a first and second ending structure, but Musescore wasn't acknowledging the first ending and instead skipping to the second ending without repeating back to the start. I am not exactly sure how to make it do what I want it to, so I'm hoping someone here can help me out. I'm going to make a little diagram of the repeat structure as I envision; please let me know if there is a better way to execute my idea than what I am currently doing.

(||: a :||: b :||) c1 :|| c2 || d, e, f, g, etc.

As you can see in this diagram, 'a' and 'b' need to repeat both times for both endings, but each repetition will have a different ending. In other words, the flow of the piece will look like [a, a, b, b, c1, a, a, b, b, c2, d.......]