How to retrieve .key from AES-128 m3u8

[limiteddi]

Curl with user agents provides contents of the m3u8 file with token but retrieving .key file fails with the same method. What are some of the tools used to see what parameters are passed to get access to the key file?

#EXTM3U
#EXT-X-VERSION:3
#EXT-X-MEDIA-SEQUENCE:12314
#EXT-X-TARGETDURATION:6
#EXT-X-KEY:METHOD=AES-128,URI="https://IP/BBC_World_News/BBC_World_News_1200-1530714520000.key",IV=0x00000000000000000000016465B1F9C0
#EXTINF:6.000,
BBC_World_News_1200-1530716404000.ts
#EXTINF:6.000,
BBC_World_News_1200-1530716412000.ts
#EXTINF:6.000,
BBC_World_News_1200-1530716416000.ts
#EXTINF:6.000,
BBC_World_News_1200-1530716424000.ts
#EXTINF:6.000,
BBC_World_News_1200-1530716430000.ts
#EXTINF:6.000,
BBC_World_News_1200-1530716436000.ts
#EXTINF:6.000,
BBC_World_News_1200-1530716442000.ts
#EXTINF:6.000,
BBC_World_News_1200-1530716446000.ts
#EXTINF:6.000,
BBC_World_News_1200-1530716454000.ts
#EXTINF:6.000,
BBC_World_News_1200-1530716460000.ts
#EXTINF:6.000,
BBC_World_News_1200-1530716464000.ts
#EXTINF:6.000,
BBC_World_News_1200-1530716472000.ts