Two weeks ago I had the same software working reliably, but it was with a different router. The previous router was a newer model, no more than a year old. The router I am using now is older. Sorry no details available, but it is worth mentioning that there are instances where the ESP won't connect even though a computer can.
Another thing that is different is that the old SSID was 9 characters whereas the new one is 3 characters. I mention this because I saw in another post that having a short SSID might be a problem.
I've also tried connecting ESP-01 to my iPhone's personal hotspot. That doesn't work either. The name has mixed case and an apostrophe in it ie "Admin's iPhone".
I've got to work on my code a bit, my CWLAP isn't properly coded, so I don't yet know what APs the ESP can see.
I second the motion regarding the CC3000. The documentation was garbage, some of the essential commands weren't even documented. You had to reverse engineer the commands by reading their driver code. And their driver code was unnecessarily verbose. It appears that TI abandoned it. They gave it up the behind to all of the people who invested their money and efforts into that part. I'd like to try the CC3100 which is the replacement chip, but can't find a small module (like the Adafruit Huzzah) with the CC3100 on it. Could it be that all those folks who made boards for the CC3000 also said "never again"?
Just because a company is big doesn't mean their staff is competent.