Ah. This is an opportunity for you to make her feel special and DHV at the same time.
"Give me a few minutes. I'll make changes to my Wunderlist. Reschedule that one. Cancel this one and this one... There you go. Let's go."
https://www.wunderlist.com/#/login
When you're out with her, she will try to reciprocate. Don't stop her from doing nice things for you. If you let her reciprocate, she will feel a deeper emotional connection with you.
Sometimes though, you'll have to be unpredictable and decline a girl's invitation. If you want to keep this girl, it's all about the emotional roller coaster ride.

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Approach. Open. Escalate. Isolate
Here are my two essential rules on texting that will save you tons of time and money:
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