If the amount is too large, the bank will report to the People's Bank of China. Mainly anti-money laundering. For details, please refer to the Anti-Money Laundering Law, the Measures for the Administration of Large and Suspicious RMB Payment Transaction Reports, the Measures for the Administration of Large and Suspicious Foreign Exchange Fund Transaction Reports of Financial Institutions, and the Anti-Money Laundering Regulations of Financial Institutions. As long as there is no problem with your funds, you are not afraid to check.