A pink Easter dress size 3X but it does run small

Purchased the gray dress and pink one in a 3X however, it is small for a 3X. It’s a pretty Easter dress not sure the material either. Description Composition : 95% Polyester, 5% Spandex Washing Instructions : Hand Wash Package Contents : 1 X Dress Style : Casual Occasion : Staycation Dress's Length : Midi Neckline : Round Neck Sleeve's Length : Three Quarters Sleeve Color Scheme : Pink Season : Summer