Also, you have rather a lot going on if you have tights,

pants,

petticoats,s and a skirt.

A change to holdups might help,

then you wouldn’t have to mess about with the waistband of the tights.

Losing the knickers also helps…

However, perhaps that’s not your style…

I suspect your best source for a straight petticoat is M&S or John Lewis if you have one locally.

Or even your local market,

they often have stalls that specialize in basics and ‘traditional’ underwear.