Banner Changes color when I create a map while trying to destry/break a banner

I discovered this bug when I try to make a map...  i didn't noticed that i'm breaking a banner... But when the map was created, the banner changed color into black.... 

 

I've tested this in other colors of the banner... And it's still the same.... I know that looks unreal but i hope you should try this in yours... If this is fixed... im so sorry

 

My device is Oppo A3s...