B bought 2000 commodities and gave them to A for the first batch of futures.
A got 2500 yuan after sale, but failed to collect the money in time, during the period.
B Raise funds for 500 yuan by itself and send the second futures (salary advance).
A sends B a down payment of 2500 yuan.
A After-sales Phase II 1000, unpaid.
B receives 2500, buys 2500 commodities and sends them to A for the third futures.
A sends B the second sales amount 1000, which B receives but does not deliver.
A will get 3,000 yuan for the third after-sales period and send it to B.
B received 3000, purchased 3000 goods and sent them to A for the fourth phase.
A sells the fourth installment of 3500 yuan and sends it to B.
In this way, A sent a total of 2500+1000+3000+3500 =10000.
B The total payment received is 2500+1000+3000+3500 =10000.
In your case, it may be because B's cash management is rather chaotic, involving the advance payment of wages and non-delivery, and personal funds and operating funds may be mixed. According to the above example, B really only has the last 3500, but he can check every money received/advanced and the purchase amount.