Problem With HLG not recognised on FireTv Stick 4K



I have a file (BBC web stream download) that has HLG format HDR.

if i play the file muxed in ts container in Kodi it plays fine and the HLG kicks in , if I mux the same file in to MP4 or MKV then HLG doesn’t kick in , I have other files that have HLG and play perfectly.

does any anybody have a solution(s)

small sample and mediainfo & ffprobe @ https://mega.nz/folder/lKQFiQ4C#-0UxlwJdYKl2Cqu97jmmxQ

thanks in advance for any assistance