What should I do?

Let it be said, I do like this girl, I have tried asking her out (twice). Each time I did though, she was legitimately working, but made no effort to reschedule. I try and be there for her, and show her I care, its obvious I like her. At one point, we started sending hearts, flirting etc, but after I started getting a little more flirty she backed off. However, she still does seem flirty at times, and like she wants to date, but then quickly pulls in. I find out she likes this other guy, but he doesn’t like her and she’s accepted it but hasn’t moved on quite yet. Should I just move on from the situation? I think I should, but at the same time, a part of me thinks I will miss out because at times she’s very flirty (she’s normally shy, so she’s not a flirty girl, which is why I feel like she likes me). I feel like she likes me, but likes him more and is holding out to see if his mind changes. Help, ideas?

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