Blackview BV9500 Fails to save pictures or videos sometimes

Hi,

My problem with the phone - it sometimes does not save pictures and videos. The picture shows on the screen while taking it. The video shows that it's being recorded. Then when I want to open it it goes black. The phone tries to open it and never does. With different programs it's the same so probably the files are broken. 

Restarting the phone didn't help. 

I tried updating android but it is the newest version. 

Then after a couple of hours it just works. The damages files show black but I can take new ones and everything works fine. Until the next time (maybe next day, maybe in 3 days).