Co worker ghosted me?

I asked for her my co worker number and she agreed. I texted her after 4 days saying : I would love to take you to a nice dinner tomorrow, what time are you free tomorrow? and guess what she ghosted me for 4 days now...

We work for different departments, so we won't be seeing each other so much.

My two questions are...

1) why would she give me her number and ghost me, and I even heard she said I am handsome from common friends.

2) how should I treat her now at work? like nothing happend? or tell her something.

Any comment will be apreciated ! thank you all

Co worker ghosted me?
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