Quick answer: A visible gap usually points to too little panel overlap or an uneven wrap. A skirt that slides down calls for a separate check of the ties, waist placement, and fabric.

A gap at the back and a skirt that keeps slipping may both look like dressing problems, but they do not always have the same cause. Identify which one happens before deciding whether to retie or exchange the skirt.

If the back opens up

Ask someone to photograph the skirt from behind while you stand, then again after you sit and walk. Are the panels overlapping but sitting off-center, or is there barely any overlap at all? If movement exposes a large section underneath, a pin or extra layer may cover it temporarily but cannot add fabric to the skirt. Compare your waist measurement with the seller’s garment measurements and ask whether another size offers more overlap.

If the skirt slides down

Check the tie path against the guide for your particular skirt, the position of the waistband, and whether the fabric is slippery. Retie it, walk for a few minutes, and note whether the ties loosen. Pulling them tighter and tighter can make sitting uncomfortable and distort the pleats.

Show the seller the specific problem

Take photos of the skirt laid flat, its tie openings, and the front and back during the try-on. Record your waist measurement and the layers underneath. “It fits while standing but gaps when I sit” gives a seller more to work with than “it doesn’t fit.” Do this while the return or exchange period is still open.