If you've started a "not as described" return the option to escalate it to ebay will appear after 3 complete working days.
If a return has been started but closed by the seller you may have used the wrong reason (eg. doesn't fit is classed as "change of mind" which sellers can refuse) or it had gone beyond the allowed 30 days. If so you will not be able to open another one. Contact your payment provider and ask for their help with a refund.