The Hong Kong Monetary Authority is Hong Kong's 'central bank'.

It defends a trading band for the Hong Kong dollar.

It bought circa 13.8bn HKD against the USD to defend the weak side (for the HKD) of the peg.

Monthly candles for the USD/HKD. You can clearly see the limits of the trading band (I posted this chart yesterday but one a monthly bar basis there is no change):

usdhkd monhly hkma intervention 15 June 2022