Phone keeps refreshing itself

[Murph]

Please help guys I cannot view my Instagram etc because it refreshes while iam still viewing a post. Even typing the keyboard will go back 

[Nicky_sam03]

Hi Murph

Apologies for the inconvenience caused

Please clear the cache of the app.

To clear an app's cache:

1. From the home screen, swipe either up or down to access apps.
2. Select Settings.
3. Select Apps.
4. Select the sort by icon next to 'Your apps'.
5. Select the switch next to 'Show system apps' and select OK.
6. Select the app you'd like.
7. Select Storage.
8. Select Clear cache.

Then soft reset the device. Press and hold the power and volume down buttons for about 10 to 15 seconds (this will not erase your data, it is just to reboot the device)