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You have to upload vector in Jpg format. Once it is accepted, you can upload the additional format using the 'Additional Format' tab in the upload area. As you click the thumbnail of the accepted photo, its file id will be added to the appropriate field and then you have to browse the corresponding vector and upload.
Following quote copied from FAQ of DTWe love illustrations! Vector files should be saved in raster format, JPG at a high resolution, saved at highest quality and submitted in this format. You can also upload an additional format (AI, PNG, CDR or EPS extensions accepted) after the JPG upload using the FTP upload/Additional sub-folder or as soon as the JPG is accepted. In some cases (e.g. layouts of web templates) it is advisable to upload the additional format before the review of the JPG file in order to increase chances of approval.
Canon EOS 1100D, 18-55mm III, 50mm f/1.8 II, Canon 80-200mm