The reason why the factoring company should be added to the repayment of the fund advance business is that in the fund advance business, the factoring company can act as the management and supervision institution of the advance, and has the following functions:

1. Risk management: Factoring companies can conduct risk assessment and supervision on prepayments to ensure the safety and stability of prepayments. At the same time, factoring companies can also evaluate the credit status of investors and provide risk-controlled financing services for fund companies.

2. Fund management: The factoring company can manage and supervise the advance funds, including the use and recovery of funds, to ensure the efficiency and compliance of the use of advance funds.

3. Asset recovery: When the investor repays, the factoring company can assist the fund company to recover the advance payment, including services such as collection and liquidation, to ensure the fund company's capital security and stable income.

4. Capital flow: Factoring companies can help fund companies realize capital flow, including services such as payment and collection of advance funds, and improve the efficiency of fund use and recovery.