我的心被你上了锁你却忘了把钥匙给我
[wŏ de xīn bèi nĭ shàng le suŏ nĭ què wàng le bă yào chí jĭ wŏ]
It means 'You put a lock on my heart, but forgot to give me the key'. This metaphor implies feelings of love or attachment from one side (the named user), while the recipient does not reciprocate the sentiment, resulting in emotional confinement or unfulfilled expectations.