使用currentPlaybackTime崩溃的问题

[HanYaChao12]

An instance 0x151469f00 of class KSYMoviePlayerController was deallocated while key value observers were still registered with it. Current observation info: <NSKeyValueObservationInfo 0x14ff3bd20> (
<NSKeyValueObservance 0x14ff47650: Observer: 0x1501b9e00, Key path: currentPlaybackTime, Options: <New: YES, Old: NO, Prior: NO> Context: 0x0, Property: 0x1513a62a0>
上边是报错信息，我复现不出来，但是这个上边说我释放了对象，我调试的时候也查看了，我并没有释放对象啊？？？怎么回事啊大佬回答一下 啊