We had several problems with that issue on our iPhone 5s, HP Notebook and Cricket service.
We found that the best and easiest way to get them to connect was to do the following.
1. turn off HP Notebook wifi (use wifi icon at lower right side of page on HP Notebook).
2. Using the iPhone, turn off wifi and personal hotspot
3. Wait 3 seconds
4. Using the iPhone, turn on the personal hotspot. The iPhone will ask if you want to also turn on the WiFi. Answer YES.
5. turn on HP Notebook wifi (use wifi icon at lower right side of page on HP Notebook).
6. The iPhone should show up as a connect option, select iPhone and connect to surf, using the HP Notebook.
After you do this several times, it only takes 5 seconds to get online, if you are dropped.