What should I do in this situation?

So, There is this girl who I really like at my university... I have tried to get close to her as to make her know me and also to know her... She got sick like 3 weeks ago I used to ask about her every now and then. Last time I asked about her she replied after 24 hours and she was online on other social media platforms... I know that she doesn`t like me back according to her behaviour. So, I want to know what should I do? Thanks in advance
What should I do in this situation?
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