Lately I've had a few cases like this of girls giving me their numbers and because of some constraint I couldn't call them for some time but I texted them to let them know. They reply and when the time comes to call them they don't answer and don't call back. In both these examples I'm almost certain to run into these girls again at some point in the future which makes this even more baffling.
Example 1: I meet this girl at a meetup but don't talk all that much. Later I run into her cause it turns out she lives in my complex. She recognizes me first. We talk a while. I get her number. We're both about to leave town (this was right before Christmas) so a few hours later I text her and tell her I'll call her after the new year and she text back that that sound great. She doesn't answer me after new year.
Example 2: This girl who plays poker at the same bar I do had given me IOIs in the past so this time I make a point to talk to her more. She gives me IOIs again. Makes a point of "saying goodbye" to me at the end of the night alone so at that point I suggest we should hang out and I get her number. I realize I'm going to be out the next 2 nights so I text her to tell her that and tell her I'll call her on the weekend. She sends a long text back and says she's free Sunday night. I call her then and she never gets back to me.