When you take a look at, depending on how your mobile addiction, you will find out that 1GB Ram and shared 8GB internal storage may not do well for your needs. Your device may begin to hang, slow or lag when playing HD games due to low run-time memory. On the other side, your P5 may reach apps installation limit or storage inadequacy for file storage.
The only solution to it is to hard reset it. Below are the simple steps to go about it.