Short answer. Yes, but only in three situations: the goods are perishable, the contract expressly reserved a right of resale, or the buyer has been in default on the price for an unreasonable time. You must also still hold a lien on the goods or have stopped them in transit.
What the law says
Where the goods are of perishable nature, or where the seller expressly reserves the right of resale in case the buyer should make default, or where the buyer has been in default in the payment of the price for an unreasonable time, an unpaid seller having a right of lien or having stopped the goods in transitu may resell the goods.
Civil Code, Article 1533 — Unpaid Seller's Right of Resale. Read the full provision →
The three doors — and the condition behind all of them
Non-payment alone is not a licence to resell. The law opens only three doors: perishable goods, an express contractual right of resale, or default for an unreasonable time. Behind every one of them sits the same precondition — you must be an unpaid seller who still has a right of lien over the goods or who has stopped them in transit. In plain terms, the goods must still be within your control or recoverable before delivery is complete. A seller who has already parted with possession and with any lien has no resale remedy under this article at all; the remaining route is an ordinary action on the contract.
What a valid resale does to your claim against the first buyer
A lawful resale cuts the original buyer out of the goods and out of the profit. The article says the seller "shall not thereafter be liable to the original buyer upon the contract of sale or for any profit made by such resale, but may recover from the buyer damages for any loss occasioned by the breach of the contract of sale." So if the goods fetch more the second time, that gain is yours to keep. If they fetch less, the shortfall and the costs you were put to are recoverable as damages from the buyer who defaulted. The new buyer, for his part, acquires a good title as against the original buyer.
Notice: not required, but rarely wise to skip
The article is explicit that notice of an intention to resell is not essential to validity, and neither is notice of the time and place of the resale. That is not the whole story. Where your right to resell rests on the buyer's default for an unreasonable time — rather than on perishability or an express clause — whether you gave notice becomes relevant evidence on the very question of whether the delay really was unreasonable. A written demand with a clear deadline is cheap, and it converts a contestable judgment call into a documented one.
The limits that catch sellers out
Two restrictions do the most damage in practice. First, you are bound to exercise reasonable care and judgment in making the resale; you may sell publicly or privately, but a careless dumping of the goods invites the buyer to attack the shortfall you are claiming. Second, you cannot, directly or indirectly, buy the goods yourself — a resale to a relative, an employee or a company you control risks being treated as no resale at all. None of this decides your particular case: whether a lien still exists, and whether a delay was unreasonable, turn on the facts and documents.