Have you noticed that your charging has slowed? I mean was it faster and now it's slower? Inconsistent charging could be a sign that your cable is damaged, or the charging port is dirty. Also you are going to charge at different rates depending on if you charge from a wall outlet or a USB device connection, i.e. via a PC or PS console. These cables may not look damaged or stop functioning but over time if one isn't careful the plug becomes loose and the connectors in the plug begin to make weak contact. This can result in poor or slowed charging, and/or the loss of being able to sync with other devices. Loose connections will also result in dirty terminals on your device which can also slow things down. If this sounds like what you are experiencing try a new cable. If you think it's just slow, you could try a higher mA charger but you may want to read up on those before doing so. Higher mA chargers can charge devices faster but can also damage batteries and increase heat during charging reducing the life of the battery. However a better alternative would be to purchase a spare battery and external charger. You will always have a fresh battery and have no charge time.
You calling issue can be device or service related. Issues like this have no real solution, sometimes a patch will come out if it is a widespread issue, but if it is that bad you may want to look into exchanging the device or having it serviced.