Exchanging bracelets with smaller ones and paying the difference in value
If what you have mentioned is meant to annul the contract and return the unsuitable bracelets then buy bracelets of a smaller size at a lower price, there is nothing wrong in this and it is not considered Riba. On the other hand, if what you have mentioned
is meant to replace the first bracelets (Part No. 13; Page No. 500) with smaller ones and pay the difference in price, then this is Riba because it is a sort of exchanging gold for gold with additional money taken.
May Allah grant us success. May peace and blessings be upon our Prophet Muhammad, his family, and Companions.