Apps not installing; new pics are disappearing & deleted pics and videos are reappearing.

[Amit Kinger]

My Lumia 1520 (OS version 8.10.14219.341) started giving me abovementioned issues a few days ago. If I am trying to install new apps or update existing apps, it is not working. It downloads but when installing, it gives me issues and error "Attention Required. Tap here". I have tried "try again", soft reset to the phone, canceling the download and try a fresh installation of that app but it is not working.

At the same time I noticed that some videos and pics which I had deleted from the phone, reappeared and took some pics yesterday have disappeared from the phone.

Can anyone please let me know the issue and answer to the issue? I do not want to hard reset my phone