@hopialikeit is correct, this is not a camera issue. We call it Lens Flare. There are various elements which cause this but since most of them does not apply on a smartphone camera, I am listing two of the most common causes of it.
Lens Dust – all lenses accumulate dust overtime and the internal dust can cause more flare issues.
Front Element Cleanliness – greasy fingers and other particles on the front element can also create more flare/ghosting issues
My recommendation is that you:
Keep your lens cover clean - this should reduce the amount of light being reflected by the dust and dirt on the lens cover
Change perspective/framing – sometimes just changing the position of the light source in your shot can make a huge difference
Hope this helps.