If the jade pendant you bought has quality problems or is inconsistent with the description of the merchant, you can request a return or exchange according to the relevant provisions of the Consumer Protection Law of People's Republic of China (PRC).

If the merchant clearly indicates on the invoice that "only exchange is not refundable", then you can try to negotiate with the merchant first, explain your situation and ask for a refund. If the merchant agrees, it can be returned.

If the merchant does not agree to return the goods, he can complain to the local consumer association or the administrative department for industry and commerce and ask for mediation or arbitration. If the dispute cannot be resolved, it can also be resolved through legal channels.

It should be noted that if you request a return for your own reasons, such as personal preference or size, then the merchant has the right to refuse the return. If you need to return the goods, you need to bear the corresponding return expenses.