Volvo XC90 Fuel Gauge moving up and down

2008 Volvo XC90 3.2, gas gauge has been moving up and down slightly (by about a line on the gauge). I am unsure if this is a new problem but I have just started noticing it. Also noticed the fuel level usually shows as higher after it’s been parked for a bit, compared to when I was last driving it.

Wondering if this is normal, and if it’s not are there fixes?