Do Fashion Nova Dresses Run True To Size?

My two shirt sets arrived in three days via normal shipping from Fashion Nova, and I couldn't have been happier as a first customer. Nevertheless, I started the return process after seeing substantial sizing discrepancies when I tried them on. Still, a vexing struggle followed. Their return portal kept telling me my order didn't exist, no matter how many times I tried. Tech support's automatic responses sent me back to the same useless site whenever I tried to get assistance. Given the current state of affairs, I kindly request that Fashion Nova promptly process my refund without further ado. Thank you.