If you’re a fan of Umamusume Pretty Derby, chances are you’ve run into the frustrating Error Code 390, which comes with a message like “There was a connection error. Error Code 390.” Whether you’re playing on mobile or PC, this issue can suddenly stop you from enjoying your races and training sessions. Fortunately, this guide walks you through step-by-step solutions that have helped other players fix the issue and get back in the game. 🔍 What Causes Umamusume Pretty Derby…