Hi....
Your first mistake was trying to use other chemicals to resolve the issue, you should have contacted the seller and explain the issue you have, if no results then you should have filed a SNAD (Significantly Not As Described) claim with PP (PayPal).
If PP finds in your favour then they would instructed you to return the item (at your own expense) for a full refund (original cost of the item and original cost of shipping...NOT the return cost of shipping.
Give it a try and file the SNAD claim, you have ONLY 45 days from time of payment to do so.