First DHglass Stevens Sidecar - received wrong joint size 14mm instead of 18mm (18mm bowl shipped)

Anyone have experience with Stevens sidecar being shipped the 14mm joint size when you order the 18mm and receive the 18mm bowl as well. Is it recommend to contact the seller or DHgate directly for support as it is my first purchase from China? Pretty bummed out I cant use it but would still recommend Stevens / CCG to anyone.

Pictures of piece: https://imgur.com/a/BuOW2

Link to piece from order summary: https://www.dhgate.com/product/2014-new-matrix-sidecar-glass-bong-birdcage/214701656.html?f=DM%7CEDM%7CShipping_en_pc%7Cseries%7CEN%7CPC%7C2018-02-28