your gnd symbol looks smaler than i would expect the kicad default one to look. Is this one made by you? If so are you aware that the pin name defines the resulting net name not the symbol name or value? See Tutorial: How to make a symbol (KiCad v5.1.x)
If that is not the case then make sure you did not connect another label or power symbol to the same net as any net can only ever have one name.l