The task of maintaining a consistent POV (point of view) can be a challenging one. It can be a vague, non-tangible object; and to handle it can often be like grabbing hold of smoke. Even seasoned writers with a name and following lose hold of it at times. Don't believe me? Pick up a copy of Larry McMurtry's 'Lonesome Dove'. In one of the opening paragraphs - the one where they're sitting around the table eating breakfast - McMurtry hops from one character's head to the other; working his way around the table.
Anyway, maintaining POV was a concept I'd think I had 'gotten'; and then poof! I'd lost it. I got more and more frustrated. And then I came up with my 'brilliant idea'. (Hey! It's been known to happen.)
I chose a scene with four characters in it, and then I wrote it four times - one from each character's perspective. It wasn't easy. Not only did it take time and effort, but if forced me to manipulate the scene to maintain that character's POV and still cover everything I still needed to happen. But it was worth it! After that, things just kind of .clicked' into place.
Now, do I have the odd slip? Yes, without a doubt. But they are few and far between; and usually, they are very minor.
And if I ever do have a total brain-freeze (which, since my sixtieth birthday last month, seems to be happening more and more) I have those four versions of the scene safely tucked away to use as a refresher course.