Subtitle not temporarily working when we hit "What did they just say?" Siri query

We have developed a custom player tvOS application using AVPlayer Foundation. When we hit the Siri command "What did they say?" Playback will go backwards but subtitles will not work temporarily. Anyone please suggest a solution for this issue :)

Subtitle not temporarily working when we hit "What did they just say?" Siri query
 
 
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