Default emoji colour keeps resetting on iOS Keyboard.

I'm having an issue with my iPhone 7 running since the time I updated it to iOS 11.1.2. It seems to show the "emoji shade" I last used on my iOS keyboard, but when I click on it - it comes up with all of the different "shades" and I have to choose the one that I want. It doesn't happen all the time, but just randomly. Ideally if I would want to choose a different shade, I would have to "long press" the emoji; but this not the case.

I have already updated to iOS 11.3, but the problem persists.