During export, a group of frames in a Figma PDF file is resized in both height and width. For example, a frame with an original size of 1080x1080 becomes 4500x4500 after export. Even if I export each frame individually as a PNG (where the size is retained as 1080x1080) and then combine them into a single file using other software, I encounter the same issue: the final size becomes 4500x4500. How can I fix this?