Power changes can result in different POIs, I have a Leupold VariX compact that is bad about this, but it's predictable and goes in the right direction, raise power from 2x to 7x and the POI raises about 2" at 200yds, so it helps in that case. It's usually prevalent in lower cost scopes, but obviously not limited to them!
If you have the parallax set wrong for the range you shoot at, it can cause POI changes due to parallax error, the markings on a scope's AO don't always correspond to what it is in reality. I adjust the AO to be free of parallax at the range I'm shooting at by setting the rifle in bags or rest and looking thru the scope and adjusting the AO until there's no movement of the reticle on the target when I move my eye position around slightly without touching the rifle. For 100yd as an example, then I make note of the position of the AO in reference to the markings or make a new index mark for that range. If there's parallax error, unless you have your eye in the exact same position each time you shoot, the impact change will show as bigger groups.
Tim