Motorola Moto G4.
All the notification icons are displaying in black making them difficult to see.
When I restart from sleep they are white but turn black after about 2 seconds.
This happened about a year or so ago but resolved itself after a couple of weeks.
This time it's been over 2 months now.
Any body know what's going on or have ideas to fix it ?
Thanks for looking.

 

I don't have a new launcher or anything else new.
They have been white from day one until now except for the instance I mentioned.

I found "Invert Colours" and added it to the swiped-down screen - however :-
It has changed everything - home screen background and all app icons, contacts and messages white on black (horrible), every screen in every app I have tried !!!!!

Can't find anything to change only notification icons.

 

I can't find any settings at all relating to the status bar. (Except what items to show).

I have never changed the wallpaper at any time.

There is no dark mode on the phone - Android 7.0 still.