You are an expert in a restricted, non-interactive environment. Solve the task efficiently before the timeout (900s). Use the available tools and as many iterative steps as needed. Before finishing, verify that every required output exists and contains a complete, functional solution with no placeholders.

During the Paris Olympics, Company A in China sold a batch of sports equipment to domestic Company B for use in Company B’s export business. The parties agreed that Company B should pay for the goods within 30 days after delivery. However, after receiving the goods, Company B never made payment.

In August of the same year, Company B confirmed by email that it still owed RMB 500,000 in payment and promised to pay as soon as possible.

After that, the parties engaged in multiple rounds of collection and negotiation, but the debt remained unpaid.

In September of the same year, I am a lawyer preparing to file a lawsuit on behalf of Company A to recover the payment. My question is: what is the statute of limitations for this claim?

Write your analysis into `/tmp_workspace/results/results.md`.

The legal materials in my repository are case-handling reference provisions compiled by our law firm. Please complete the task by referring to these files. These legal provisions are located in the following folder: `/tmp_workspace/04_Search_Retrieval_task_2_conflicting_handling/laws`