Background being stuck in night time(IOS)

Even at the day time, background never change from night time. I’ve tried re-installing, deleting safari cookies, and even re-starting cell-phone for a several times but it does not fix anything. This bug really disturbs my sight and annoying. Please instrust me some effective solutions as soon as possible.

If my interpretation is correct, it will be resolved by the end of the week. It is not a bug, but a staged October weekend.
*However, I’ve heard quite a few people say it’s too dark this year.