The Shenzhen Stock Exchange issued an inquiry letter to Yingjianke's annual report, requesting the company to explain the reasons for the downward trend in revenue after listing; explain the timeliness and accuracy of preparation of individual accounts receivable and the authenticity of related sales; explain the reasons for the extension of accounts receivable and the increase in the share of accounts receivable in the same industry; the ratio of the company's accounts receivable within and outside the credit period in 2023; the authenticity and recyclability of accounts receivable outside the credit period and the collection measures the company plans to take. Explain the reason and rationality of the sharp increase in R&D investment as a share of revenue since 2021, the transformation of results from R&D investment, and the relationship with the company's business development.