The only way I managed to upload my file was by splitting it into parts. Since I needed to upload multiple textures, it was easier to divide them. I split them into three separate files, and the upload was successful that way. However, when I tried uploading everything as a single file (even though it was well under the upload limit), I kept getting an error. I’m not sure of a workaround for uploading a file that can’t be divided into parts, hopefully Epic will address this in a future update.