闭上 pronounced pei-soeng in Cantonese: just Wang Jie in this song or something more?
It is '门若闭上了 便再会无期'
闭 only has one Cantonese Jyutping /bai3/ , and it is never pronounced as /pei3/ . Wang Jie pronounced it wrong.
譬, 屁, 媲, 嬖 all pronounced as /pei3/,  but none of them carry the meaning of 'close'

上 is pronounced as /soeng6/ when it is used as a noun or an adjective
e.g. upper, superior, previous

~

上 is pronounced as /soeng5/ when it is used as a verb or verb particle indicating direction or achievement

'上' in '闭上' is a verb particle indicating achievement (close shut)
therefore '闭上' is pronounced as /bai3 soeng5/